ROCKS grade Calcium Carbide
NUT Grade Calcium Carbide for large lamps
Nut grade is ROCKS size, which is larger chunks than the pea size, from 3/8" to 1 1/4". PEA size is commonly used in smaller lamps like those on miner's caps. ROCKS are usually used in the larger lamps, like car lamps, railroad lamps. bicycle and motorcycle lamps, hand lamps, and acetylene generator units.