The difference between a big flying wrench and a small flying wrench refers to the size of the joint between the handle and the sleeve of various types of sleeves.

By size:

Small fly 6.3mm, medium fly 9.5mm, large fly 12.5mm, Xiao Fei is especially suitable for small-sized sleeve elastic nuts below 14 mm, and Fei Zhong is suitable for matching sleeves within 24 mm. Large fly has relatively large torque and is suitable for working with sleeves within 32 mm

Material classification of casing:

Divided into Cr-Mo steel, Cr-V steel and 45 # steel. Chromium-molybdenum steel is an alloy of chromium, molybdenum, iron and carbon, which has good high-temperature cutting performance, beautiful appearance after machining, large quenching depth and good impact absorption, so it is often used in manufacturing pneumatic tools and large hand tools in industry. Cr-V steel is an alloy tool steel containing Cr-V alloy elements, which is mainly used for hand tools. 45 # steel has become a common processing material in steel because of its good machinability and multi-directional processing technology.