Series 92 Adapter Type Available in sizes from 5/16" thru 19/32" diameters, these flue brushes are made in carbon steel, stainless steel, nylon or brass filament. 8-32 threaded adapters are attached for use with extensions. The brushes feature double stem, double spiral construction for maximum filament density. Flue brushes are ideal for removing soot and carbon deposits from pipes and for cleaning tube sheets For more information please visit our website here:https://www.newmantools.com/brush/series-90brushes.htm Stainless Fill Catalog Number Actual Brush Diameter BR-92S312 5/16" BR-92S344 11/32" BR-92S375 3/8" BR-92S437 7/16" BR-92S500 1/2" BR-92S562 9/16" BR-92S594 19/32" Hi-Temp. Carbon St. Catalog Number Actual Brush Diameter BR-92C312 5/16" BR-92C344 11/32" BR-92C375 3/8" BR-92C437 7/16" BR-92C500 1/2" BR-92C562 9/16" BR-92C594 19/32" 6-12 Nylon Catalog Number Actual Brush Diameter BR-92N312 5/16" BR-92N344 11/32" BR-92N375 3/8" BR-92N437 7/16" BR-92N500 1/2" BR-92N562 9/16" BR-92N594 19/32" Brass Fill Catalog Number Actual Brush Diameter BR-92B312 5/16" BR-92B344 11/32" BR-92B375 3/8" BR-92B437 7/16" BR-92B500 1/2" BR-92B562 9/16" BR-92B594 19/32"