More than happy with results. Was able to repair the base of my expensive Bose L1 Classic PA speaker which I had dropped and cracked the case and two internal screw mounts. I used the black power to repair the broken mounts inside of the case and beefed them up with so they are very strong; perhaps stronger than before, but hope not to test. I then used the black powder to repair the cracked base; doesn't look perfect but is smooth to the touch after filing and sanding. See before and after photos. I forgot to take photos of the repaired mounts before reassembly; may do at a later time.