1、High quality steel is stable and durable, help you save energy, use with wrench, suitable for mountain bike crankshaft, very suitable for bicycle maintenance. 2、Bicycle chain disassembler, hook lock ring tool and bottom bracket assembly tool in one, multi‑functional 3 in 1 wrench, used to remove and install the flywheel and shaft. 3、Crank puller removal used to remove chain rings and cranks, combined with a wrench to remove the crank unplug tool, freewheel cassette remover with 20 teech used for remove the bottom bracket of the bicycle. 4、The bicycle chain cutter is specially designed for removing and installing chain bolts, rotary flywheel remover can be used to tighten flywheels, suitable for 8, 9 and 10 speed cassettes. 5、16 in 1 function bicycle tools: socket hex wrench 8/9/10/mm, slotted screwdriver, cross screwdriver, socket extension rod, solid wrench 8/10/15/mm, hex key wrench 2/2.5/3/4/5/6mm and spoke wrench, help you to fix many problems.