This 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. Great for use within tight, narrow areas in applications where losing a bristle could create a problem. This high-quality brush has a 1 x 11 row configuration, with a 7/16" trim, and a brush face of 1-1/8" x 1/8". These thin-faced brushes are popular for cleaning, scrubbing, wiping or dirt removal in delicate applications. Autoclavable for cleanroom, sterile, or medical applications. Meets FDA 21 CFR 177.2480 and ASTM D6100 standards. RoHS 3 (2015/863/EU) compliant.