I copied/pasted this info:
This system supplies more than twice the ultra-violet exposure than conventional sterilizers making it our first choice in UV technology. Patented helix design forces water to make a double-spiral pass along the entire length of the PowerCompact UV lamp. This Helix UV technology provides unprecedented 36" and 60" of Ultra-Violet exposure. Revolutionary space age polymer prevents adhesion of algae and other particulate matter inside the reaction chamber. Power-Compact Ultraviolet lamps last twice as long as standard fluorescent bulbs.
18watt
16 1/2 in. x 3 3/4 in.
up to 350gph
5/8 in. inlet & outlet
Recommended for up to 250 gallon aquariums
