Colour: Silver M8Size: 4.7 x 2 cm Pulls ring spring piston: this quick release pen is small and portable, convenient and easy to take to any place you need. Button pestle: high hardness, wear and rust, longer service life. Pack of 4 Pull Ring Locking Bolts Positioning Pin Rings Pull Locking Bolts with Pull Ring Machine Knob Pestle Made of Stainless Steel Spring Stainless Steel 304 Positioning Post Pulls ring spring piston: this quick release pen is small and portable, convenient and easy to take to any place you need. Button pestle: high hardness, wear and rust, longer service life. Non-lockable locking piston: piston body, pin and pull ring made of stainless steel for safety and durability, can be used for a long time. Piston pin with pull ring: made of stainless steel materials, not easy to deform or break, you can use with confidence. OSALADI