100 x 200mm (x 40mm height) finned Aluminium extrusion for heatsinking 3W LEDs.
Just right for two 15 or 18 LED PCBs, for a total of up to 36 LEDs, or about 60W, with active cooling.
For passive cooling, it is a little bit wider than the 80x200mm heatsink, so would be better if you want a passively cooled full spectrum LED light, but probably unnecessary for other 3W LEDs.
