Review on 🔩 Collated Fasteners: Z Threaded Hex Flanged Internal Threads Fasteners by Tony Reid

If you intend to use them to attach speakers to a box then the speaker hole cutout must be perfectly square. You will need to use a router and jig to cut the hole. The hole should be as narrow as possible to provide enough wood for this insert. If you are using them to mount them from the inside so that the speaker is pressed against the baffle you will need to use a drill guide to keep the drill bit perfectly perpendicular to the speaker baffle or the hole will be disabled and the screws will cross either the threads or push out the insert. Also check each insert as some of them are not drilled perfectly in the center. Found multiple deviations by several degrees. Very frustrating.