Secure, slip-free locking: The spring-clip collar firmly locks the pin in place so it will not slip during intense workouts. Fast, reliable locking lets you change weight settings quickly for efficient training sessions. Durable iron construction: Made from long-lasting iron with a robust 2-ring spring-clip collar for dependable strength and consistent performance in both commercial gyms and home setups. Versatile compatibility: Designed to work with a wide range of fitness equipment, including weight stack machines and home gym systems. Also usable as an extender pin to safely expand your available weight options. Safety-focused design: The secure clip reduces the risk of accidental release, helping you train with fewer distractions and lower injury risk. Key attributes Function: Locks weight stack pins securely; also functions as an extender pin to increase usable resistance. Material: Durable iron body with a two-ring spring-clip collar. Performance: Stable under heavy use; enables quick weight adjustments and reliable retention during dynamic movements. Suitable environments: Commercial fitness facilities and home gyms. Practical use scenarios 1) Commercial gym cable/weight stack machines: Replace worn or missing pins to restore safe, reliable operation and allow staff and members to change weight selections quickly. 2) Home multi-gym systems: Use as a direct replacement pin or as an extender pin to expand the range of selectable weights for progressive training. 3) Circuit or high-intensity workouts: Securely lock plates or weight stacks between sets so athletes can move quickly between stations without worrying about pin slippage. What you get A sturdy weight-stack/extension pin with a two-ring spring-clip collar that prioritizes safety, compatibility, and long-term durability for both professional and personal training environments.