This is a set of draft gear key slots with keys, enough to apply the detail to four cars. Hopefully the sprue will hold up, but it is also the mounting pin, if you want to use it for that. It may be easier to mount without the pin. The mounting pin is .060", so you can use a 1/16" drill to make the hole for it. This is a detail that is left off by many modelers, but is very visible, particularly when you have done a lot of work to a particular car. This is fairly generic, but is applicable to a wide variety of equipment ... with the exception of the Trinity 5161 Covered hopper. That and its smaller cousins, use a lipless slot for the draft gear key, so it wouldn't be appropriate for that.