Chain guide for bicycle stabilizers: easy installation and removal; includes a chain guard cover for the front chainring, enabling quick setup and removal for everyday use. Chain guide to prevent chain drop on bicycles: this chain tensioner can convert multi-speed bikes into single-speed bikes; features an aluminum alloy chain guard for durability and reliable performance. Crankset/chainring guard: lightweight design that does not affect your riding experience; safe and reliable chain management to protect the drive system. Derailleur protector: constructed from aluminum alloy and nylon; built to withstand rugged outdoor environments and provide effective bicycle chain protection. Use scenarios - City commuting with frequent gear changes: install to prevent chain drop and improve drivetrain security on rough pavement or potholes. - Drivetrain simplification: convert a multi-speed bike into a single-speed setup for maintenance simplicity or track-style riding. - Rugged outdoor riding: protect the chain and derailleur from debris, impacts, and harsh conditions in off-road or adventure riding. Materials and attributes - Aluminum alloy components for strength and durability - Nylon elements for resilience in rough environments - Lightweight design to minimize impact on performance - Easy installation and removal for flexible use across setups