This thing protects the idler pulley on my kmx cobra trike from dirt spray from the front wheels. I believe this is the place where the chain picks up most of the dirt, at least I removed quite a lot from there during the last service. It's somewhat parametric, but I don't think it makes any sense for anything other than a adult-sized kmx trike (2012 and later), so that's probably irrelevant. Photos are coming soon.Attach with zip-ties.