Brush Seater, 4-3/4X 3/8 in X 3/8 in, Grade Fs For cleaning commutator pick a stone about 3/4 the length of the commutator bar and as thick as will neatly fit between the brushing rigs. For best results, use a stone with a width equal to or greater than the width of the brush. To use the Brush Seater, hold close to the brush so that Brush Seater material will be carried under the brush..
.2 in X 1 in X 1-1/2 in, Commstone, Grade Ec With Straight Handle Stone mounted on a straight handle for difficult to reach commutator When compared to turning tools commstones are easier to use, more time effective, and remove less copper.