Features: Engineered for high tension performances, this single speed chain tensioner features aluminum alloys construction with ceramic inner rings, ensuring greater impacts resistance than traditional cast iron while maintaining precise chain alignment for mountain bikes. The innovative tool quickly release enables 10 second installations, with a sealing spring mechanism that prevents mud ingress and reliability operations during intense cycling. Designed specifically for aggressive trail riders and downhill enthusiasts, this derailleur pulley accommodates both hardtail and full suspension frames, making it ideal for cyclists prioritizing durability in various environment. Optimized for technical descents and terrains, the 11T guide pulley maintains consistent chain tension across rock gardens and drop offs while reducing drivetrain noise by 30% through its precisions engineered aluminum ceramic composite structure. Compatibility with single speed mountain bike brands, this chain tensioner combines weather resistant materials with a modulars design. Specifications: Color:Five Choices Dimension:4.5cm/1.77in 5cm/1.97in Component:Aluminum alloys Package Includes: 1pc Single Speed Chain Tensioner note: 1.Please allow 1-2cm errors due to manual measurement, making sure that you will not mind before order. 2.Due to the differences between different monitors, the picture may not reflect the actual color.