MCTi Mountain MTB Bike Rear Derailleur Jockey Wheel Titanium Allen Hex Flat Head Bolts Screw M5 4 Packed Size: M5x15.5mm Allen Hex Flat Head; Color Available: Colorful,Gold,Ti Material: 6AL/4V (TC4) Titanium Alloy, Grade 5; Weight: 1.18g/piece. Thread Pitch: 0.8mm; Thread Diameter: 5mm; Head Diameter: 7.32mm; Head Height: 1.72mm; Key Size: 3mm; MCTi Brand Trademark Bolt is with high performance, corrosion-resistant, light weight, high strength and durability functions. Original Brand Packed. Many applications especially in sports, mountain bike, bicycle, motorcycle, automotive, racing, aerospace, medical industry and DIY areas.