High Quality Material: This weight stack pin is made of durable solid steel, safe and reliable, with a black coating to prevent product corrosion and rust. Product Features: Our weight stack pin is simple and easy to use, just insert it into the weight stack machine and adjust the weight according to your exercise needs. It can help you strengthen your workouts to achieve fitness goals and gain better body shape and muscle strength Product Specifications: The package includes weight pins and spring clip collars. The weight stack pin counterweight area is designed for 2-inch Olympic barbell plates to help your weight machine load extra Olympic weight and let your muscles continue to accept new challenges! Multi-functional Applications: It is not only a weight stack pin but also a weight stack extender. It can enhance your home gym experience without bulky equipment, and can also be used as a gift for people who like fitness and strength training. 【Purchase Instructions】Please measure the cable stack pin diameter before selection to ensure perfect compatibility. Gym pin comes in 5/16" (8 mm) or 3/8" (10 mm) slots. (8mm gympin for 9-10mm diameter fitness equipment, 10mm gympin for 11-12mm diameter fitness equipment) Weight Stack Pin Extender Set Weight Stack Extenders to upgrade your multi training machine, designed to add extra barbell weight to the extender for training purposes. Weight Stacking Pin Size Series Pin Dia 10mm x Length 110mm Pin Dia 8mm x Length 110mm How to Choose the Right Gym Pin Size 8mm gympin is suitable for fitness equipment with a diameter of 9-10mm 10mm gympin is suitable for fitness equipment with a diameter of 11-12mm