Trim-Tex Dual Angle Sanding Sponges 885F - IMPERFECTS

Features two tapered edges to simplify corner sanding and radius edges to prevent gouging and scuffing of compound. 40% larger than standard blocks, measuring 5" x 3 ¼".

What is the difference between a regular and an Imperfect sponge? 
Imperfect sponges are the offcuts, the ones that are a bit rougher around the edge of cuts or slightly crooked. Minor traits that make them a bit more 'imperfect' than the regular cut sponges.