Drive: DIN 3120, ISO 1174, Form A 6.3 + A 10. Application: Extension for the ESD screwdriver handle and MicroBits Bits: Reduced, over-turned profile. Standards: for bits DIN 3126, ISO 1173, Form C4 The extension is compatible with the ESD screwdriver handle and the MicroBits. It can also be used to reach deep-set screws. DIN 3126, ISO 1173, Form C4.