BB80MB is a large donut format module with heatsink included. Typically, no OEM heatsink is required at 40C ambient if mounted in aluminum or steel pan. The LEDs are spread out to run cool and provide even illumination in pendants, close-to-ceiling and similar round format luminaires. The module has a 5.22" center opening for placement of drivers inside to reduce shadows on lens and 12” leads to connect to driver. If other than Permlight driver is used, contact email@example.com for driver warranty and compatibility.