Square D® NF Merchandised Panelboards MH38, is a enclosure steel panelboard box has NEMA1 degree of protection, cULus certified. Warranty period is 18 month. This is a powerbus accessory is end closure for the busway rated at 225 A. Square D® NF Merchandised Panelboards MH38, is a enclosure steel panelboard box has NEMA1 degree of protection, cULus certified. Warranty period is 18 month. This is a powerbus accessory is end closure for the busway rated at 225 A.