Check the listing for details. Dye Proto Paintball Primo Gravity Feed Loader Hopper - Black (Used). Condition: Used. Listed at 12.50 USD. The Proto Primo Loader does not require any batteries in order to feed paint. This version of the Proto Primo loader is the first of its kind with a positive feed shelf built in. This is there in order to relieve pressure on the paint which allows for an increased feed rate and less jams.