Thread Size: 5/16-2Stainless Steel Cylinder Exclusive manufacturing process ensures a slick cylinder inerior for smooth plunger tip movement. Includes friction-free teflon tip as well as long-lasting metal tip 3 different strength springs included includes　1.5mm and 2.5mm hex wrenches Can be fastened even more securely with SHIBUYA Plunger/Stabilizer spanner (sold separately) Colors: Black, Silver, Blue, Red, Gold