The Park Tool MT-40 is a high quality folding take-along bike tool that features all the essential tools needed for an on-the-ride adjustment or emergency repair. The MT-40 features a selection of hex and star driver wrenches for most bolts and fittings found on a bicycle, as well as a universal screwdriver for derailleur adjustment. Also features a chain breaker tool for emergency chain repair and replacement, and a CO₂ cartridge inflator adaptor to assist in reinflating flat tires — compatible with most bicycle tubes with a Presta valve.

Built with forged aluminum side plates and hardened and plated tools to withstand years of use. With its compact size, the MT-40 is the perfect size for a saddle bag or backpack.