THIS IS A GREAT BRUSH FOR DOING A LOT OF JOBS REALTED TO SOLDERING COOPER PIPE AND CLEANING UP THE TERMINALS OF BATTERIES AND SO ONE. IT DOES A SUPER JOB GETTING COPPER PIPE CLEAN AND READY TO BE SOLDERED. IT ALSO DOES A GREAT JOB CLEANING A VARIETY OF TERMINALS WHERE WIRES WILL BE ATTACHED. THE COST IS $6.75 BUT $7 IS SHOWN BECAUSE OF THE SYSTEM .