1.The product is based on Chinese Forestery Standards LY/T 1187-1996. 2.The professional chain for woodcutters who use electric saws , such as 5012,5014,5016 High Profile Cutters, Sharp Blade, longer Chain Life, Pre-added Lubrication before producing, running smoothly, less retractility. Grind chain after assembly, more wearable Made in super Nickel Alloy, The Best Cutting Capability, Better Impact Resistance. Slantwise Limit Tooth, Reducing Recoil. Maintain Conveniently, Working With Facility.