Welcome to our store! 1. Application: The heavy-duty M9x0.75 to 1/2-28 adapter is designed as a replacement for Sig Sauer 1911 22, GSG 1911 22, 5PK 22, and some others that have M9x0.75 threads. 2. Flat Ridges Design: The M9x0.75 to 1/2-28 threaded adapter comes with flat ridges for easy installation removal with a wrench (not included), enhancing operational efficiency. 3. With Thread Protector: The M9x0.75 to 1/2-28 adapter is equipped with a 1/2-28 thread protector to guard the 1/2-28 thread for use without accessories or for storage. 4. Knurl Design: The 1/2-28 thread protector is professionally designed with a fine diamond ring, looks attractive and stylish, and has greater friction to prevent slipping. 5. Durable Construction: The M9x0.75 to 1/2-28 converter with thread protector is constructed from premium high-carbon steel with a black oxide finish, not easy to rust, very durable in use. Item Type: M9x0.75 to 1/2-28 Adapter Material: High-carbon steel Barrel End Thread: M9 (9mm) x 0.75mm Adapter Outer Diameter Thread: 1/2-28 Cap Fully Screwed In Length: Approx. 1.25in / 3.2cm Maximum Diameter (with cap installed): Approx. 5/8in / 1.59cm Fitment: For Sig Sauer 1911 22, GSG 1911 22, 5PK 22, and some others that have M9x0.75 threads. 1 x M9x0.75 to 1/2-28 Adapter Customers are our top priority. If you find any problems with your product after receiving it, such as damage or incorrect quantity, please contact us immediately. We strive to provide you with the best after-sales service.