This Replacement for Venture Lighting 19824 MH400W/U/ED28/PS/740 is a 400W pulse start metal halide HID lamp designed for reliable, high-output performance in commercial and industrial lighting applications. Featuring an E39 mogul base and ED28 bulb design, it installs easily into compatible fixtures using M135 or M155/E ballast systems. Delivering approximately 39,600 lumens of 4000K bright white light, this lamp provides strong, consistent illumination ideal for warehouses, manufacturing facilities, gymnasiums, retail spaces, and other large-area lighting applications. The pulse start design helps support efficient operation and dependable light output. With a rated life of up to 22,500 hours, this HID replacement bulb offers long-lasting durability, reduced maintenance, and reliable performance in demanding lighting environments.