The diamond grinding cup that came with the dust shroud worked well (better than I expected). The instructions were a little vague in places. First had to try multiple 'adapters' (supplied) so the dust collector would connect tightly to my Hitachi grinder. Had to adjust the small nut on the clamp adapter several times to made sure it was 'tight' to the grinder. Then had to figure out how to get the grinding cup properly mounted onto the grinder. Took a few tries to get the 'washer disks' correctly placed on both sides of the cup and then tighten into place. When setting-up the attachment to my Shop Vac, I ended up removing the rigid tube from the end of the flex hose on the Vac, and then inserting one end of the rubber 'hose adapter' into the end of the hose, then taping it in place with Duct Tape. The dust collector worked pretty well - except when the hose adapter popped out of the collector housing and the dust quickly spread outward. Had to be careful and check the connection multiple of times to try and keep that from happening again. I used the dust collector and the diamond grinding cup on my Hitachi angle grinder to grind down 'high' spots from a poured concrete floor. When the concrete floor was originally poured/finished, it was apparently 'hand troweled' rather than machine troweled and had multiple 'high' spots in it (some a good 3/16" to 1/4" high). Previously this floor had carpet padding and plus pile carpet installed over it, so any such 'high' spots were not noticeable. I am installing a high quality, 9" wide vinyl plank flooring over the concrete and when I first cut and laid the flooring, some of the planks would not 'interlock' with adjacent planks (both along the long sides and on the ends) due to height variations on the underlying cement. I ended up removing all the new flooring planks, then checked the floor for 'high' spots/areas using both an 8' 'straight edge' and a 4' aluminum level, marked the high areas and commenced grinding...checking every few minutes to ensure I hadn't gone down too far. Lots of work (and will be lots of cleanup later), but now the new flooring should install just fine and I shouldn't have any issues about planks not 'interlocking'.