I went through THREE of the 4-spools in the shipment, for ONE JOB (managed to cut my small yard before the 3rd wire ran out unexpectedly)! I was cutting my front yard, which with the Black & Decker factory-made product, I was able to cut my back, side, AND large back yard with ONE SPOOL. The problem I had with this product I ordered was, it did not "snap" into place like the B&D factory-made product, which made the spool unravel to the point I had to constantly stop to take the spool out and "reSee full review