RMS Track

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Tanks come in a lot of shapes and sizes. To accommodate the vast majority of commercially available and custom aquariums the RMS multi-light rails start at 20.5 inches and increase in 10 inch increments to 90.5 inch. The multi-light RMS allows for adjustment of the rail with respect to the arms – meaning that even if your tank is not a common length – there is a rail length that will work for you."