Designed to cover a huge horizontal growing area, the Lightning XXXL Reflectors focus lumen output with highly reflective materials and an aerodynamic design. The Lightning XXXL includes a quick locking glass shield that gently opens, closes, and creates a tight seal for optimal cooling. It also features a standard E39 socket for compatibility with most bulbs. While most large reflectors require you to slide a huge glass shield in or out of place for bulb maintenance, we've made it easy and stress free while adding excellent ventilation capability.