This light has been redesigned (it has a new cap and o-ring) so that the bulb is easier to replace.  Aquascape also filled the base with epoxy so that water can't leak through the cord entry.

It can be completely submerged in the water for under-water lighting or you can use the included stake and fasteners to mount it out of the water.  It comes with a 15' cord, but it does not include the transformer (click here for pond transformers).

This 20 watt light comes with a 1 year warranty.

If you want something a little more colorful, check out these cool colored replacement lenses.

PDF instructions for the Aquascape 20-Watt Hex Head Light