This brush has 0.010" Medium-stiff Static Dissipative Nylon Bristle with a Static Dissipative Acetal handle. The Nylon fill material is hand-laced with Nylon twine into its handle for maximum fiber retention. It can be used for cleaning or scrubbing applications in confined, static-sensitive areas. The handle is no more than 3/8" wide at the brush end. RoHS 3 (2015/863/EU) compliant. For other brush size options within this series using 0.010" static dissipative Nylon, see parts: 11S9X, 22S9X