got the electric TRIndustrial 300 demo hammer a few years back from Amazon that served me well removing stone + concrete, fast forward i wanted to change the bit that was a pain but got it out + proceeded with the wider bit BUT the front section that retains bit came apart in use. i "think" i found all parts BUT maybe as bit comes out in use + looking for a parts list + diagram with no luck!! gotta check as i usually save all paperwork + looking for any links or suggestions as google is NOT helping, thanks in advance for any help.