6 PCS Black Electrical Tape, 19mm X 20m Strong Self-Adhesive PVC Insulation Tape for Electrical Wiring, Repair and Protection

£7.59 at time of order, the price is about right. I've been sad enough to unroll an entire spool and you do indeed get 20metres of tape on a roll and it is 19mm wide. It separates from the roll easily. The adhesive is good and it sticks well. You get enough stretch to get a nice tight wrap around a connection and it doesn't break easily when pulled taut. They are individually wrapped although the reverse is not entirely enclosed on some of the rolls so you may pick up some lint and toolbox crud on the edges but that is a very minor niggle.

Decent tape if you're looking to tidy up some wiring - I've just fitted an aftermarket head unit in my car and the spaghetti of wires was an eyesore so got this tape to clean it up. Being a 6 pack I didn't panic on how much I was using which is usually the case. Tape isn't too thin and wasn't tearing om stretching it so no complaints from me. Worth considering if you've already looked this far...