procedure TForm371.Button1Click(Sender: TObject);
var
  KeyArray: TBytes;
  iv: TBytes;
  mmIV: TAESBlock;
  clearText: TBytes;
  aad:  TBytes;
  ciphertext: TBytes;
begin
 KeyArray := [$11, $11, $11, $11, $11, $11, $11, $11, $11, $11, $11, $11, $11, $11, $11, $11];

 iv := [$4D, $45, $54, $00, $00, $00, $00, $01, $00, $00, $00, $00];
 FillChar(mmIv, 16, 0);
 System.Move(iv[0], mmIv, System.Length(iv) );

 cleartext := [$0f, $c0, $00, $00, $01, $0c, $07, $e6, $09, $1a, $01, $03, $27, $2e, $5a, $ff, $88, $80, $02, $02, $09, $06, $00, $01, $19, $09, $00, $ff, $01, $01, $02, $06, $09, $0c, $07, $e6, $09, $1a, $01, $03, $23, $00, $00, $ff, $88, $80, $11, $5a, $17, $49, $cb, $25, $1d, $17, $49, $cb, $25, $1d, $17, $49, $cb, $25, $1d, $17, $49, $cb, $25, $1d];
 aad := [$30, $33, $33, $33, $33, $33, $33, $33, $33, $33, $33, $33, $33, $33, $33, $33, $33];

 setlength(ciphertext, length(cleartext));

 var mAES := TAESGCM.Create(KeyArray);
 mAES.IV := mmIv;

 mAES.Encrypt(nil, nil, 0);
 // Comment / Uncomment for AAD
 // mAES.AesGcmAad(@aad[0], System.Length(aad));

 var rawciphertext := mAES.EncryptPkcs7(Convert(cleartext));
 Move(rawciphertext[1], ciphertext[0], length(rawciphertext));

 var checktag : TAESBlock;
 mAES.AesGcmFinal(checktag);