One small tradition that we’ve seemingly adopted from the Americans is the use of patches and pins to signify our beliefs ideas or to inform fellow soldiers about which regiment, blood type or rank, which need not be signified with patches or pins on the front of your uniform, these usually go either on the sleeve or on some tags tucked onto your undergarments.
Source: https://prodailyinfo.wordpress.com/2018/05/16/morale-patches-military-civilian-identifiers/
