This stiff insulative brush has 0.012" Stiff Nylon Bristle with a Delrin (Acetal) handle. The Nylon fill material is hand-laced with Nylon twine into its handle for maximum fiber retention. This high-quality brush has a 3 x 11 row configuration, with a 7/16" trim, and a brush face of 1-1/4" x 5/16". These brushes are popular for cleaning, scrubbing, wiping or dirt removal in delicate applications. These brushes can be used in an anti-static environment when submerged in liquid. Autoclavable for cleanroom, sterile, or medical applications. Meets FDA 21 CFR 177.2480 and ASTM D6100 standards. For fine detail work requiring very soft nylon bristles, see part # 33ND-003.