The Simpson Strong-Tie ETBR-EXT T-handle and extension are required for use with all sizes of rebar nylon brushes. Simpson nylon ETBR rebar brushes are used for cleaning holes before adhesive installation. They are designed with longer lengths and stronger construction to clean holes drilled for deeper rebar embedments. To obtain the total usable length, add the usable length for each part used. The rebar brushes are intended to be used with Simpson Strong-Tie® SET-XP® and SET-3G™ adhesive.