Protects the chain from falling off and extends the life of narrow and wide chainrings. A practical accessory for mountain bikes, road bikes, and MTBs. Key benefits - Prevents chain derailment on rough terrain, improving reliability and rider confidence - Extends the life of narrow and wide chainrings by reducing wear and impact - Versatile for different bike types and gearing systems Compatibility and specifications - Mounting: ISCG 05 bracket - Hole spacing: 55.92 mm - Disc diameter references: Disc 30T approximately 128 mm; Disc 40T approximately 168 mm Chainring compatibility and adjustability - Suitable for narrow and wide 30-40T chainrings (round chainrings) - Suitable for 30-38T chainrings (oval chainrings) - Adjustable design using spacers to set the distance of the upper part - Do not use with screws What is included - 1 x 4 mm Allen key - 1 x 3 mm Allen key - 9 x stainless steel spacers (diameter 12 mm, thickness approx. 1.5 mm) - 2 x M6 x 10 mm screws Material and construction - Made of high quality aluminum alloy with nylon guide block - Features: sturdy, lightweight, rust-proof, deformation resistant, durable Use scenarios - Off-road riding on rough trails with narrow-wide or wide-range chainrings to prevent chain drops - Road cycling using 30-38T oval chainrings to maintain chain retention and drivetrain longevity - Bike maintenance or setup where precise spacer adjustment is needed for optimal upper-part distance