Rugged, efficient shaker eliminates hand sieving. Automatically duplicates horizontal circle-and-tap agitation necessary to grade soils and aggregates before further testing. LA-0406 holds 6°Full height or 13 half-height 8 in (20.3°Cm) diameter sieves plus pan and cover. Vertically-mounted 1/4 hp motor drive mechanism is enclosed to protect against dust damage. Automatic thirty minute timer allows comparable results between two or more tests. Timer shuts unit off at end of test interval.