the Chew basket) with gnaw bones available, a selection of Cow knee-joints and other bones.
Every now and then I "refill" the basket, by throwing/putting out maybe 10 to 20 (or more) new hard-pressed/other sorts of bones either on the floor or hidden around the house, after a few hours when they have stopped gnawing, I collect what's left and put in the basket.
Gnawing keeps their teeth clean and they enjoy doing it, so I try to make sure they "eat"/gnaw one bone a day. Depends on what sort it is of course, a knee-joint doesn't disappear on one day even if they cooperate.
Things like Pig ears they get one each and they know there's no point in quarreling to try and steal the others because I will step in and stop them, they can exchange (I take yours and you take mine), but I don't allow them to both eat their own and steal somebody else's. In the unlikely case that somebody doesn't eat f. ex. all of their Pig ear, piece of Bull penis, I take what's left back, because putting 1 small piece of Pig ear in the Chew basket that 3 dogs shares would be to ask for trouble.
Other bones I always make sure there's more than one of, because f. ex. it makes it much easier for them to accept that I might ask them to give me their bone when they're surrounded by ten or more other bones, why should they have serious quarrels in between themselves over one bone when they're surrounded by ten or more other bones...