The SeligerĀ® Quellstar 900 is a 9 Watt LED nozzle that can be inserted into cored rocks and other drilled water features to create a brightly lit, brilliantly hidden water jet. The Quellstar 900 measures 1.9" diameter x 3" high, fits 1" tubing, and fits snugly into holes 50mm in diameter. Can be used in water temperatures 32-104 degrees Fahrenheit.