Strong-Tie ETBS-EXT 12" Extension for ETBS-TH T-Handle, Pkg 1The Simpson Strong Tie ETBS EXT extension is a 12" extension for the ETBS TH T handle. This extension is designed for use with the Simpson ETBS wire hole cleaning brushes. These brushes are excellent for cleaning drilled holes before installing adhesive anchors. The brush head is designed for use with the Simpson SET 3G adhesive. To obtain the total usable length, add the usable length for each part used.