Open-weight safety classification models
1 in the catalogue today, and the list grows as the market does. Every one with what it costs, who sells it and where it stands.
Models that classify content rather than produce it: what is unsafe, what breaks a policy, what should not be shown. They sit in front of or behind a bigger model, are small and cheap by design, and are the part of a system nobody notices until it is wrong. The thing to check is what the model was trained to catch, because policies differ and a guard tuned for one product's rules will be strict in the wrong places for yours.
Weights published under a licence that lets you run them where you like and sell what you build — Apache 2.0, MIT and their kin impose little beyond keeping the notice. This is the list to start from if you need the model on your own hardware, in your own region, or simply want no third party between you and it. The trade is that hosting is now your problem, and the prices shown beside each one are what somebody else charges to do it for you.