This is a rare and highly sought-after 16-inch ribbed barrel for the TC Thompson Contender. The barrel is designed for use with both 410 bore and 45 long colt ammunition, making it a versatile addition to any handgun. There is NO CHOKE KEY. It is made by the reputable brand Thompson and is perfect for hunting or sporting activities. The barrel is made of high-quality materials and is in excellent condition. It is a great investment for anyone who wants to improve their shooting performance.