This is one of the big guys… Sun System's Large Super Horizontal reflector measures 20-1/2 inches long and 24 inches wide, covering large areas even when hung close to plants. Yet it only weighs 7 pounds! 

95% reflective German aluminum offers excellent reflectivity, plus the sides of this reflector are angled for further extended coverage. Louvered on both sides to help it run cool for longer life, the Large Super Horizontal can easily be converted to "air cooled" by adding optional fittings with 4-inch ducting, optional tempered glass lens and an exhaust fan to circulate the heated air.

Sun System Large Super Horizontal dimensions: 20-1/2" Long x 24" Wide x 7.5" High
Weight: 7 lbs

UL listed for use with Sun System® Brand Fixtures.
(Does not include ballast, cordset or bulb.)