Bristles are secured in a PVC block 3.5" long, 1.5" wide and 0.5" thick, and are uniformly trimmed to a length of 0.75"
Total brush weight is 2.5 ounces which is 1.5 ounces lighter than current metal-backed brushes. To compensate for this difference a 1/16 inch thick stainless steel plate is furnished with each new brush that may be inserted in the brush box above the brush.
After a long period of use bristles will wear down below the original length of 3/4".
Brush bristles should be periodically measured and if they reach a shortened length of 5/8", we suggest they be disposed of.
The shorter the bristle, the firmer it is. The firmer the bristle, the more harsh the performance.