Can tell you a little about 2 Cav names the first letter tells you what sqn the veh belongs to all A sqn names start with A , B for B sqn, Tek support Sqn ( also know as LAD) started with T, C for C sqn as Dennis says C sqn was added after they moved to Darwin. The black triangle means A Sqn, a black square was B Sqn and a circle was C sqn .