No, the ones I use are made from some kind of plastic and they don't have a precut thread internally.

I don't know what sort of plastic/nylon? they are made from but I have tested them with epoxy and it does stick.

They are designed for drywalls, but I have used them for fittings on rotomoulded boats (additional toestraps, deckclips to take bungee, spinnaker ratchets). More recently I used them to fit the aft toeloops on the Stealth.