... patent for that technology.Circuit explanation for HID special energy-saving lamps electronic ballast: Second bridge topology circuit structure and the ... reliability,high performance and much longer life. The special energy-saving light bulbs for special use can get up to 70% ... , square, factory, oil field,etc. Type 420 mining lampHID75GK-BHID150GK-B Bulb type:G90-E40/E27(ball shape, phosphor powder ...