STACO 3-phase 480V WYE variac with 4 coils per phase, 0-560V output with type 52LA paralleling chokes, 50 or 60 Hz input and a closed case. This variac was custom-ordered with 480VAC WYE input and a slower motor instead of the standard 60-second motor. CA Inventory # 6563

Motorized 480VAC input 0-360 output variable transformer made by Electro Engineering Works in San Leandro, CA. THIS IS NOT A CONSUMER ITEM.  Tested working. Some documentation (see pictures).  it is a 480-volt unit. Manufactured by Electro Engineering Works, San Leandro, CaliforniaInput 480VAC single-phase 68A continuous, 100A intermittentOutput 0-360VAC, single-phase 80A continuous, 88A intermittentCA Inventory # 5662

FEATURES: Manufactured by Superior Electric Co. in Bristol, ConnecticutType 1256D (Spec BP142090)Input Single-Phase, 240V 50/60 HzOutput 0-280V, 28A, 7.8kVA72 lbs raw weight, 15"x15"x9.5" CONDITION: Looks lightly used, in good condition. Works well.  You can check out connections and ratings for this unit and many other types at the Superior Electric website. CA Inventory # 5550