A. PAD-LOK™ Heavy polypropylene strands trimmed offset at 1/2" are staple set in our TUFF-BLOCK®, making this the superior tufted pad driver choice. Tufts penetrate into the pad for secure holding power. Includes our 1-1/2" thick plastic riser at no additional cost! Compare to current or past OEM associations: Prochem 8.600-029.0 Legacy 02418 Windsor 8600029.0