For those of you who may wish to purchase additional carriers (the wheels with the hook) you can call Imperial Fastener at 954-782-7130. We talked with them and they indicated that they have track and carriers that are compatible with the Ontrax System.
Note that this was not our manufacturer; we have not confirmed compatibility.
As the photography industry continues to evolve, we wish all of the best to photographers everywhere. I am proud and honored to have been a part of this most gratifying profession.