The rules that use the vocabulary item "propelled" are:

<i_f_v-sing>

self propelled 82mm mortar

self propelled eighty two mortar

<i_f_v-pl>

self propelled 82mm mortars

self propelled eighty two mortars

<i_f_v>

self propelled 82mm mortar

self propelled 82mm mortars

self propelled eighty two mortar

self propelled eighty two mortars