diff --git a/types/bytebuffer/index.d.ts b/types/bytebuffer/index.d.ts
index fca26b439f..0ed98f54c6 100644
--- a/types/bytebuffer/index.d.ts
+++ b/types/bytebuffer/index.d.ts
@@ -307,6 +307,11 @@ declare class ByteBuffer
      */
     readByte( offset?: number ): number;
 
+    /**
+     * Reads the specified number of bytes
+     */
+    readBytes( length: number, offset?: number): ByteBuffer;
+
     /**
      * Reads a NULL-terminated UTF8 encoded string. For this to work the string read must not contain any NULL characters itself.
      */
@@ -508,6 +513,11 @@ declare class ByteBuffer
      */
     writeByte( value: number, offset?: number ): ByteBuffer;
 
+    /**
+     * Writes an array of bytes. This is an alias for append
+     */
+    writeBytes( source: ByteBuffer | ArrayBuffer | Uint8Array | string, encoding?: string | number, offset?: number ): ByteBuffer;
+
     /**
      * Writes a NULL-terminated UTF8 encoded string. For this to work the specified string must not contain any NULL characters itself.
      */