Product Specifications: Length: Approx. 7.9 inches (20 cm), Inner Diameter: 0.2 inches (6.9 mm), Outer Diameter: 1/4 inches (6.35 mm), 2 minutes; 8.3 mm (Outer Diameter: 5/16 inches, 7.93 mm), Outer Diameter: 0.4 inches (10 mm), For 4 minutes, Outer Diameter: 5/8 inches (15.8 mm). 0.3 in (8 mm) for 5
Material: Spring Steel
Caution: If it is difficult to fall off, simply unscrew it by rotating it or pull it out with a tension that does not stretch in the direction of the inner diameter spreads.Pulling it out may extend the spring and shorter its life.