Not ''C's''....But......
I was an RTO......So when resupply dropped off extra batteries for my Prick 10....Everyone wanted the thick plastic bag the battery came in....
So the trade/deal was 'If you wanted the bag you carried the extra battery till i needed it.... [They were like a brick and heavy] Once i needed it i would bayonet the old battery and give the bag to the mule who carried the new battery .....