Size length 50mm, size for manual measurement, there may be a 1-3 mm deviation, belongs to the normal phenomenon.
Material made of high-grade S2 steel material, professional fast convenient, powerful and high precision made.
Advantages magnetic Hex Shank can suck the screws easily when used it, which will highly improve your efficiency that manual.
Tips at home, use a multi-purpose oil, like three-in-one, and slow speed. The drill bit will still get hot, though, so let it rest a while before changing it or you'll likely burn your fingers.
Application it can be used with an electric screwdriver, electric drill, group general tools, etc.