Material: Titanium alloy
Size: 51mm * 36mm * 9.7mm
Finger hole diameter: 24mm
Weight: about 40.7g
A single-finger titanium ring in hedgehog design — about 40.7g, 51mm built for keychain EDC. The 24mm finger hole locks it on your hand; curved spines and a sharpened tip concentrate impact, while one contoured edge pops bottle caps. Titanium keeps it light, rust-proof, and hypoallergenic. Unlike a four-finger knuckle, it rides on a keyring until you need it.