C.K 422001 Size 1-2 Modulo Screw Driver Insertion Bits

Having been frustrated by the difficulty of tigtening the clamping screws on such as RCBs and contactors, due to the screws having a cross-head indentaion plus a slot, I Googled to see if a special bit was available, and I found these.The bits do the job well, but on some screws, which are down a hole over 1cm deep, the hex part of the shank won't fit down the hole, which stops them reaching the screw! I fixed this by putting a bit in the 3 jaw chuck of my lathe and turned back the hex part about 1cm to lengthen the cylindirical part (had to use a carbide insert for this). After that, these bits really a pleasure to use - they self-locate well and make it easy to feel when a screw is properly tight. One could achieve the same effect using a small angle grinder. HTH, J

This is the set I was looking for. Lots of connections have this type of bolds (PZS)and to use a electric screwdriver you need this bits to get it propper tighten.The material is very stabile and last long.

Broke first time using it. And the time spent returning it isnt worth the hassle

Fantastic bits! I bought extra sets after my initial purchase!!!!

Tighten rcbo, MCB with these heads are very easy and quick

It's CK - that's good. They are supplied very quickly - even better.

Good for nipping up, but when you put them in torque screwdriver, as you should for consumer unit, they are not that well made and slip. Better quality ones don,t slip in same consumer unit.

Ok