A moving fixture will distribute light more evenly over your plants. It eliminates shading and allows more even growth and development. The Hydrofarm Light Track does just this: it slowly moves your fixture back and forth along its length, simulating the effect of the sun travelling across the sky. It takes about 14 minutes to travel 4 feet. Features: Silent, lifetime lubricated motor, Heavy-duty four wheel carrier, Pre-wired with 9 foot power cord. Available in 4 or 6 lengths tracks that require an additional foot on each end for fixture clearance. Includes mounting & hanging hardware Illustrated instructions. SHIPPING NOTE: Because of its size, this item can only be shipped via UPS. UPS also treats this item as if it weighs much more than it really does. Because of this, we may be able to ship several Light Tracks together for little or no additional shipping charge. If you are planning to order multiple Light Tracks, feel free to contact us to see if we can save you money on shipping.