diff --git a/index.d.ts b/index.d.ts
new file mode 100644
index 0000000..588920d
--- /dev/null
+++ b/index.d.ts
@@ -0,0 +1,71 @@
+import { S3Client, StorageClass, ServerSideEncryption } from '@aws-sdk/client-s3';
+import { S3 } from 'aws-sdk';
+
+declare type ACL =
+  | 'private'
+  | 'public-read'
+  | 'public-read-write'
+  | 'aws-exec-read'
+  | 'authenticated-read'
+  | 'bucket-owner-read'
+  | 'bucket-owner-full-control'
+  | 'log-delivery-write';
+
+declare type ContentDisposition =
+  | 'inline'
+  | 'attachment'
+  | 'form-data'
+  | 'signal'
+  | 'alert'
+  | 'icon'
+  | 'render'
+  | 'recipient-list-history'
+  | 'session'
+  | 'aib'
+  | 'early-session'
+  | 'recipient-list'
+  | 'notification'
+  | 'by-reference'
+  | 'info-package'
+  | 'recording-session';
+
+declare interface MulterOptions {
+  s3: S3Client | S3;
+  bucket: string;
+  key(req: any, file: any, cb: (...args: any) => any): void;
+  metadata?(req: any, file: any, cb: (...args: any) => any): void;
+  acl?: ACL;
+  cacheControl?: string;
+  contentType?: typeof autoContentType | typeof defaultContentType;
+  storageClass?: StorageClass;
+  contentDisposition?: ContentDisposition;
+  serverSideEncryption?: ServerSideEncryption;
+  contentEncoding?: string;
+}
+
+declare function _exports(opts: MulterOptions): S3Storage;
+declare namespace _exports {
+  export { autoContentType as AUTO_CONTENT_TYPE };
+  export { defaultContentType as DEFAULT_CONTENT_TYPE };
+}
+export = _exports;
+declare function S3Storage(opts: any): void;
+declare class S3Storage {
+  constructor(opts: any);
+  s3: any;
+  getBucket: any;
+  getKey: any;
+  getAcl: any;
+  getContentType: any;
+  getMetadata: any;
+  getCacheControl: any;
+  getContentDisposition: any;
+  getContentEncoding: any;
+  getStorageClass: any;
+  getSSE: any;
+  getSSEKMS: any;
+  _handleFile(req: any, file: any, cb: any): void;
+  _removeFile(req: any, file: any, cb: any): void;
+}
+declare function autoContentType(req: any, file: any, cb: (...args: any) => any): void;
+declare function defaultContentType(req: any, file: any, cb: (...args: any) => any): void;
diff --git a/package-lock.json b/package-lock.json
index 6d8f601..03f6adb 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -27,7 +27,16 @@
         "node": ">= 12.0.0"
       },
       "peerDependencies": {
-        "@aws-sdk/client-s3": "^3.0.0"
+        "@aws-sdk/client-s3": "^3.0.0",
+        "aws-sdk": "^2.0.0"
+      },
+      "peerDependenciesMeta": {
+        "@aws-sdk/client-s3": {
+          "optional": true
+        },
+        "aws-sdk": {
+          "optional": true
+        }
       }
     },
     "node_modules/@aws-crypto/crc32": {
@@ -1473,6 +1482,73 @@
         "lodash": "^4.17.14"
       }
     },
+    "node_modules/aws-sdk": {
+      "version": "2.1146.0",
+      "resolved": "https://registry.npmjs.org/aws-sdk/-/aws-sdk-2.1146.0.tgz",
+      "integrity": "sha512-lg83hvrK2oiJVnklUVMXIJkeYX2nlqhvxIFlZ2wfoaJyvdGsEcOUdZ/EMDgiS0V2jwGS8CtTUypcW/t2S6gdcQ==",
+      "optional": true,
+      "peer": true,
+      "dependencies": {
+        "buffer": "4.9.2",
+        "events": "1.1.1",
+        "ieee754": "1.1.13",
+        "jmespath": "0.16.0",
+        "querystring": "0.2.0",
+        "sax": "1.2.1",
+        "url": "0.10.3",
+        "uuid": "8.0.0",
+        "xml2js": "0.4.19"
+      },
+      "engines": {
+        "node": ">= 10.0.0"
+      }
+    },
+    "node_modules/aws-sdk/node_modules/buffer": {
+      "version": "4.9.2",
+      "resolved": "https://registry.npmjs.org/buffer/-/buffer-4.9.2.tgz",
+      "integrity": "sha512-xq+q3SRMOxGivLhBNaUdC64hDTQwejJ+H0T/NB1XMtTVEwNTrfFF3gAxiyW0Bu/xWEGhjVKgUcMhCrUy2+uCWg==",
+      "optional": true,
+      "peer": true,
+      "dependencies": {
+        "base64-js": "^1.0.2",
+        "ieee754": "^1.1.4",
+        "isarray": "^1.0.0"
+      }
+    },
+    "node_modules/aws-sdk/node_modules/events": {
+      "version": "1.1.1",
+      "resolved": "https://registry.npmjs.org/events/-/events-1.1.1.tgz",
+      "integrity": "sha512-kEcvvCBByWXGnZy6JUlgAp2gBIUjfCAV6P6TgT1/aaQKcmuAEC4OZTV1I4EWQLz2gxZw76atuVyvHhTxvi0Flw==",
+      "optional": true,
+      "peer": true,
+      "engines": {
+        "node": ">=0.4.x"
+      }
+    },
+    "node_modules/aws-sdk/node_modules/ieee754": {
+      "version": "1.1.13",
+      "resolved": "https://registry.npmjs.org/ieee754/-/ieee754-1.1.13.tgz",
+      "integrity": "sha512-4vf7I2LYV/HaWerSo3XmlMkp5eZ83i+/CDluXi/IGTs/O1sejBNhTtnxzmRZfvOUqj7lZjqHkeTvpgSFDlWZTg==",
+      "optional": true,
+      "peer": true
+    },
+    "node_modules/aws-sdk/node_modules/isarray": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/isarray/-/isarray-1.0.0.tgz",
+      "integrity": "sha512-VLghIWNM6ELQzo7zwmcg0NmTVyWKYjvIeM83yjp0wRDTmUnrM678fQbcKBo6n2CJEF0szoG//ytg+TKla89ALQ==",
+      "optional": true,
+      "peer": true
+    },
+    "node_modules/aws-sdk/node_modules/uuid": {
+      "version": "8.0.0",
+      "resolved": "https://registry.npmjs.org/uuid/-/uuid-8.0.0.tgz",
+      "integrity": "sha512-jOXGuXZAWdsTH7eZLtyXMqUb9EcWMGZNbL9YcGBJl4MH4nrxHmZJhEHvyLFrkxo+28uLb/NYRcStH48fnD0Vzw==",
+      "optional": true,
+      "peer": true,
+      "bin": {
+        "uuid": "dist/bin/uuid"
+      }
+    },
     "node_modules/babel-code-frame": {
       "version": "6.26.0",
       "resolved": "https://registry.npmjs.org/babel-code-frame/-/babel-code-frame-6.26.0.tgz",
@@ -3795,6 +3871,16 @@
         "node": "*"
       }
     },
+    "node_modules/jmespath": {
+      "version": "0.16.0",
+      "resolved": "https://registry.npmjs.org/jmespath/-/jmespath-0.16.0.tgz",
+      "integrity": "sha512-9FzQjJ7MATs1tSpnco1K6ayiYE3figslrXA72G2HQ/n76RzvYlofyi5QM+iX4YRs/pu3yzxlVQSST23+dMDknw==",
+      "optional": true,
+      "peer": true,
+      "engines": {
+        "node": ">= 0.6.0"
+      }
+    },
     "node_modules/js-beautify": {
       "version": "1.14.3",
       "resolved": "https://registry.npmjs.org/js-beautify/-/js-beautify-1.14.3.tgz",
@@ -4805,6 +4891,13 @@
       "integrity": "sha1-8FKijacOYYkX7wqKw0wa5aaChrM=",
       "dev": true
     },
+    "node_modules/punycode": {
+      "version": "1.3.2",
+      "resolved": "https://registry.npmjs.org/punycode/-/punycode-1.3.2.tgz",
+      "integrity": "sha1-llOgNvt8HuQjQvIyXM7v6jkmxI0=",
+      "optional": true,
+      "peer": true
+    },
     "node_modules/q": {
       "version": "1.5.1",
       "resolved": "https://registry.npmjs.org/q/-/q-1.5.1.tgz",
@@ -4830,6 +4923,17 @@
         "url": "https://github.com/sponsors/ljharb"
       }
     },
+    "node_modules/querystring": {
+      "version": "0.2.0",
+      "resolved": "https://registry.npmjs.org/querystring/-/querystring-0.2.0.tgz",
+      "integrity": "sha1-sgmEkgO7Jd+CDadW50cAWHhSFiA=",
+      "deprecated": "The querystring API is considered Legacy. new code should use the URLSearchParams API instead.",
+      "optional": true,
+      "peer": true,
+      "engines": {
+        "node": ">=0.4.x"
+      }
+    },
     "node_modules/queue-microtask": {
       "version": "1.2.3",
       "resolved": "https://registry.npmjs.org/queue-microtask/-/queue-microtask-1.2.3.tgz",
@@ -5253,6 +5357,13 @@
       "integrity": "sha512-YZo3K82SD7Riyi0E1EQPojLz7kpepnSQI9IyPbHHg1XXXevb5dJI7tpyN2ADxGcQbHG7vcyRHk0cbwqcQriUtg==",
       "dev": true
     },
+    "node_modules/sax": {
+      "version": "1.2.1",
+      "resolved": "https://registry.npmjs.org/sax/-/sax-1.2.1.tgz",
+      "integrity": "sha1-e45lYZCyKOgaZq6nSEgNgozS03o=",
+      "optional": true,
+      "peer": true
+    },
     "node_modules/semver": {
       "version": "5.7.1",
       "resolved": "https://registry.npmjs.org/semver/-/semver-5.7.1.tgz",
@@ -5813,6 +5924,17 @@
         "node": ">= 0.8"
       }
     },
+    "node_modules/url": {
+      "version": "0.10.3",
+      "resolved": "https://registry.npmjs.org/url/-/url-0.10.3.tgz",
+      "integrity": "sha1-Ah5NnHcF8hu/N9A861h2dAJ3TGQ=",
+      "optional": true,
+      "peer": true,
+      "dependencies": {
+        "punycode": "1.3.2",
+        "querystring": "0.2.0"
+      }
+    },
     "node_modules/user-home": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/user-home/-/user-home-2.0.0.tgz",
@@ -5911,6 +6033,27 @@
       "integrity": "sha1-AJY9aXsq3wwYXE4E5zF0upsojrI=",
       "dev": true
     },
+    "node_modules/xml2js": {
+      "version": "0.4.19",
+      "resolved": "https://registry.npmjs.org/xml2js/-/xml2js-0.4.19.tgz",
+      "integrity": "sha512-esZnJZJOiJR9wWKMyuvSE1y6Dq5LCuJanqhxslH2bxM6duahNZ+HMpCLhBQGZkbX6xRf8x1Y2eJlgt2q3qo49Q==",
+      "optional": true,
+      "peer": true,
+      "dependencies": {
+        "sax": ">=0.6.0",
+        "xmlbuilder": "~9.0.1"
+      }
+    },
+    "node_modules/xmlbuilder": {
+      "version": "9.0.7",
+      "resolved": "https://registry.npmjs.org/xmlbuilder/-/xmlbuilder-9.0.7.tgz",
+      "integrity": "sha1-Ey7mPS7FVlxVfiD0wi35rKaGsQ0=",
+      "optional": true,
+      "peer": true,
+      "engines": {
+        "node": ">=4.0"
+      }
+    },
     "node_modules/xtend": {
       "version": "4.0.2",
       "resolved": "https://registry.npmjs.org/xtend/-/xtend-4.0.2.tgz",
@@ -7176,6 +7319,66 @@
         "lodash": "^4.17.14"
       }
     },
+    "aws-sdk": {
+      "version": "2.1146.0",
+      "resolved": "https://registry.npmjs.org/aws-sdk/-/aws-sdk-2.1146.0.tgz",
+      "integrity": "sha512-lg83hvrK2oiJVnklUVMXIJkeYX2nlqhvxIFlZ2wfoaJyvdGsEcOUdZ/EMDgiS0V2jwGS8CtTUypcW/t2S6gdcQ==",
+      "optional": true,
+      "peer": true,
+      "requires": {
+        "buffer": "4.9.2",
+        "events": "1.1.1",
+        "ieee754": "1.1.13",
+        "jmespath": "0.16.0",
+        "querystring": "0.2.0",
+        "sax": "1.2.1",
+        "url": "0.10.3",
+        "uuid": "8.0.0",
+        "xml2js": "0.4.19"
+      },
+      "dependencies": {
+        "buffer": {
+          "version": "4.9.2",
+          "resolved": "https://registry.npmjs.org/buffer/-/buffer-4.9.2.tgz",
+          "integrity": "sha512-xq+q3SRMOxGivLhBNaUdC64hDTQwejJ+H0T/NB1XMtTVEwNTrfFF3gAxiyW0Bu/xWEGhjVKgUcMhCrUy2+uCWg==",
+          "optional": true,
+          "peer": true,
+          "requires": {
+            "base64-js": "^1.0.2",
+            "ieee754": "^1.1.4",
+            "isarray": "^1.0.0"
+          }
+        },
+        "events": {
+          "version": "1.1.1",
+          "resolved": "https://registry.npmjs.org/events/-/events-1.1.1.tgz",
+          "integrity": "sha512-kEcvvCBByWXGnZy6JUlgAp2gBIUjfCAV6P6TgT1/aaQKcmuAEC4OZTV1I4EWQLz2gxZw76atuVyvHhTxvi0Flw==",
+          "optional": true,
+          "peer": true
+        },
+        "ieee754": {
+          "version": "1.1.13",
+          "resolved": "https://registry.npmjs.org/ieee754/-/ieee754-1.1.13.tgz",
+          "integrity": "sha512-4vf7I2LYV/HaWerSo3XmlMkp5eZ83i+/CDluXi/IGTs/O1sejBNhTtnxzmRZfvOUqj7lZjqHkeTvpgSFDlWZTg==",
+          "optional": true,
+          "peer": true
+        },
+        "isarray": {
+          "version": "1.0.0",
+          "resolved": "https://registry.npmjs.org/isarray/-/isarray-1.0.0.tgz",
+          "integrity": "sha512-VLghIWNM6ELQzo7zwmcg0NmTVyWKYjvIeM83yjp0wRDTmUnrM678fQbcKBo6n2CJEF0szoG//ytg+TKla89ALQ==",
+          "optional": true,
+          "peer": true
+        },
+        "uuid": {
+          "version": "8.0.0",
+          "resolved": "https://registry.npmjs.org/uuid/-/uuid-8.0.0.tgz",
+          "integrity": "sha512-jOXGuXZAWdsTH7eZLtyXMqUb9EcWMGZNbL9YcGBJl4MH4nrxHmZJhEHvyLFrkxo+28uLb/NYRcStH48fnD0Vzw==",
+          "optional": true,
+          "peer": true
+        }
+      }
+    },
     "babel-code-frame": {
       "version": "6.26.0",
       "resolved": "https://registry.npmjs.org/babel-code-frame/-/babel-code-frame-6.26.0.tgz",
@@ -9128,6 +9331,13 @@
         }
       }
     },
+    "jmespath": {
+      "version": "0.16.0",
+      "resolved": "https://registry.npmjs.org/jmespath/-/jmespath-0.16.0.tgz",
+      "integrity": "sha512-9FzQjJ7MATs1tSpnco1K6ayiYE3figslrXA72G2HQ/n76RzvYlofyi5QM+iX4YRs/pu3yzxlVQSST23+dMDknw==",
+      "optional": true,
+      "peer": true
+    },
     "js-beautify": {
       "version": "1.14.3",
       "resolved": "https://registry.npmjs.org/js-beautify/-/js-beautify-1.14.3.tgz",
@@ -9978,6 +10188,13 @@
       "integrity": "sha1-8FKijacOYYkX7wqKw0wa5aaChrM=",
       "dev": true
     },
+    "punycode": {
+      "version": "1.3.2",
+      "resolved": "https://registry.npmjs.org/punycode/-/punycode-1.3.2.tgz",
+      "integrity": "sha1-llOgNvt8HuQjQvIyXM7v6jkmxI0=",
+      "optional": true,
+      "peer": true
+    },
     "q": {
       "version": "1.5.1",
       "resolved": "https://registry.npmjs.org/q/-/q-1.5.1.tgz",
@@ -9993,6 +10210,13 @@
         "side-channel": "^1.0.4"
       }
     },
+    "querystring": {
+      "version": "0.2.0",
+      "resolved": "https://registry.npmjs.org/querystring/-/querystring-0.2.0.tgz",
+      "integrity": "sha1-sgmEkgO7Jd+CDadW50cAWHhSFiA=",
+      "optional": true,
+      "peer": true
+    },
     "queue-microtask": {
       "version": "1.2.3",
       "resolved": "https://registry.npmjs.org/queue-microtask/-/queue-microtask-1.2.3.tgz",
@@ -10312,6 +10536,13 @@
       "integrity": "sha512-YZo3K82SD7Riyi0E1EQPojLz7kpepnSQI9IyPbHHg1XXXevb5dJI7tpyN2ADxGcQbHG7vcyRHk0cbwqcQriUtg==",
       "dev": true
     },
+    "sax": {
+      "version": "1.2.1",
+      "resolved": "https://registry.npmjs.org/sax/-/sax-1.2.1.tgz",
+      "integrity": "sha1-e45lYZCyKOgaZq6nSEgNgozS03o=",
+      "optional": true,
+      "peer": true
+    },
     "semver": {
       "version": "5.7.1",
       "resolved": "https://registry.npmjs.org/semver/-/semver-5.7.1.tgz",
@@ -10774,6 +11005,17 @@
       "integrity": "sha1-sr9O6FFKrmFltIF4KdIbLvSZBOw=",
       "dev": true
     },
+    "url": {
+      "version": "0.10.3",
+      "resolved": "https://registry.npmjs.org/url/-/url-0.10.3.tgz",
+      "integrity": "sha1-Ah5NnHcF8hu/N9A861h2dAJ3TGQ=",
+      "optional": true,
+      "peer": true,
+      "requires": {
+        "punycode": "1.3.2",
+        "querystring": "0.2.0"
+      }
+    },
     "user-home": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/user-home/-/user-home-2.0.0.tgz",
@@ -10848,6 +11090,24 @@
       "integrity": "sha1-AJY9aXsq3wwYXE4E5zF0upsojrI=",
       "dev": true
     },
+    "xml2js": {
+      "version": "0.4.19",
+      "resolved": "https://registry.npmjs.org/xml2js/-/xml2js-0.4.19.tgz",
+      "integrity": "sha512-esZnJZJOiJR9wWKMyuvSE1y6Dq5LCuJanqhxslH2bxM6duahNZ+HMpCLhBQGZkbX6xRf8x1Y2eJlgt2q3qo49Q==",
+      "optional": true,
+      "peer": true,
+      "requires": {
+        "sax": ">=0.6.0",
+        "xmlbuilder": "~9.0.1"
+      }
+    },
+    "xmlbuilder": {
+      "version": "9.0.7",
+      "resolved": "https://registry.npmjs.org/xmlbuilder/-/xmlbuilder-9.0.7.tgz",
+      "integrity": "sha1-Ey7mPS7FVlxVfiD0wi35rKaGsQ0=",
+      "optional": true,
+      "peer": true
+    },
     "xtend": {
       "version": "4.0.2",
       "resolved": "https://registry.npmjs.org/xtend/-/xtend-4.0.2.tgz",
diff --git a/package.json b/package.json
index e1a31a1..f2e9b31 100644
--- a/package.json
+++ b/package.json
@@ -32,8 +32,17 @@
     "run-parallel": "^1.1.6"
   },
   "peerDependencies": {
+    "aws-sdk": "^2.0.0",
     "@aws-sdk/client-s3": "^3.0.0"
   },
+  "peerDependenciesMeta": {
+    "aws-sdk": {
+      "optional": true
+    },
+    "@aws-sdk/client-s3": {
+      "optional": true
+    }
+  },
   "devDependencies": {
     "express": "^4.13.1",
     "form-data": "^1.0.0-rc3",