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

<hour-not_initial_zero>

six

one six

<specific_platoon_type-creatable-sing>

brdm2 recon six

<hour>

six

oh six

zero six

one six

<digit-not_zero>

six

<digit-pl>

six

<digit>

six

<digit-not_zero-pl>

six

<specific_platoon_type-not_creatable-sing>

brdm2 recon six

<up_to_six>

six

<specific_platoon_type-sing>

brdm2 recon six