8 1/2'' overall length x 5 3/8'' wide tank brush, polypropylene block filled medium-soft red polyester, resin set, for cleaning tanks, vats and gullies. The only side not filled is where the handle fits. Compared to the #D77, this version sacrifices some coverage to accommodate the resin set process. If you require coverage as a priority, please consider the standard #D77. Recommended handles, #ALH27 or ALH8. A stiffer version is available, #D79RES.