Feature 1. High purity aluminium forming shell, aluminum alloy cast electric box with high strength, which benefits for heat emanation. 2. Imported high purity aluminum reflector with oxidized surface, high efficiency reflection 3. High intensity glass 5mm cover 4. Silicon rubber seal ring. 5. Lamp base and appliances be separate that benefit for extending the life 6. Applicable for buildings, work sites, stations and stock sites Measurement(mm) D E H L M N GT180 426 356 587 495 206 12 GT181 412 356 588 496 206 12 APPLICABLE LAMP TYPE FOR LAMP POWER(W) VOLTAGE(V) BASE GT180/181-J175 MH175ED 175 220 E40 GT180/181-J250 MH250ED 250 220 E40 GT180/181-J400 MH400ED 400 220 E40 GT180/181-N250 HPS250T 250 220 E40 GT180/181-N400 HPS400T 400 220 E40