This powder measure dispenses charge after charge of powder with consistent accuracy to a fraction of a grain. The key to unfailing precision is the 55's unique three-slide micrometer adjustable cavity. Extra-fine adjustments of width and depth provide consistent charges with almost any powder. A 2400 grain reservoir resists chemical reaction and protects your powder from harmful light rays. Mount the 55 on your bench or any turret press. No funnel is required. Includes a 7/8" X 14 thread adapter for press or stand mounting. Until the mid 1970's Lyman recommended this powder measure for BLACK POWDER! Lyman no longer recommends this. I personally use this along with our optional replacement brass hopper for loading. I do not weigh my charges except to set the powder measure. Properly used I consistently get thrown charges +/- 2/10's (.2) of a grain. This has been a proven winning combination to 1000 yards!