These Stop Bit Head Replacements for our Onboard Dust Extractors feature tool-free attachment. Easily change or replace in seconds. When a Bit Head wears out, just remove it, snap on a new one, and keep working. Use them with our DEWALT® DWH303DH or D25303DH Onboard Dust ExtractorS as part of an OSHA Table-1 compliant solution when installing virtually any concrete anchor system, including MINI-UNDERCUT+™ and Smart DI+™.