An interesting idea but does it work? We took a sample along to professional restoration workshops & they immediately placed their orders. " The only shrinking hammer I’ve tried that actually works." was the comment of one experienced body man. The spirally milled face of the hammer is mounted with vulcanised rubber against an angled adaptor. Upon impact the head grips the surface & twists causing the metal to shrink. This unique tool will prove to be a boon to anyone in panel forming or repair. Read " 10 MUST-HAVE Restoration Tools " from Technical Article.