Nut and bolt joints are an alternative to the traditional cotter pin joint. Using a nyloc ring within the nut they are easier to get a tight fitting joint.

A bear will usually require five joints.
Therefore:
A pack of 10 joints will be enough for two bears.
A pack of 50 joints will be enough for ten bears .
A pack of 100 joints will be enough for 20 bears.

Each 15mm joints consist of two fibreboard discs, two washers and one short M3 nut and bolt.

18mm joints and above consist of two hardboard discs, two washers and a nut and bolt. Sizes 18mm - 35mm use an M3 bolt and sizes 38 and above use an M5 bolt.

Be aware that you do not want to undo the nut too many times as you will begin to reduce the locking capability of the nylon ring.