H1 globes have a round base, with an "angled cut" across one side. They have two raised nibs that allow the bulb to lock securely in place, in their socket. H1 HID bulbs come in all colour temperatures (Kelvin rating) in our Supervision kits, but only 4300k or 6000k in our Philips kits. The H1 bulbs will last around 3000 hours if driven by a 35 watt ballast, or around 2000 hours with a 55 watt ballast. H1 bulbs can be used on both CANBUS and NON-CANBUS bikes.