Many people do not realize this, but the circuit boards used in many different aftermarket alarm remotes are actually the same. Aftermarket alarm systems are consumer electronics products. Like many consumer electronics products, each alarm system tends to have a short life cycle. Aftermarket alarm system manufacturers compete with features, not underlying remote transmission technology.
So, many different aftermarket alarm remotes actually use the same circuit board or the same signal transmission chips on a circuit board that is only cosmetically different. That is why one Audiovox product sold by RUI will replace more than fifteen different Audiovox and Code Alarm transmitters, several of which look very different than the part that replaces them. (Note: Code Alarm was acquired by Audiovox, so it is not surprising that the product lines have some overlap.)
In some cases, the same transmission technology is used on brands that are totally unrelated to one another. So don’t be surprised if one of the available replacement remotes for your aftermarket alarm system is a keyfob that carries a different brand on the case.