The Joule is designed for use in high-radiation areas. Its surface is super-smooth for thorough claning; it has no exposed threads or crevices to catch radioactive debris, and no sharp edges to tear workers' clothing even the interior of the Joule has no corners - only radii.

The Joule relamps in 60 seconds without tools, with inexpensive and readily available replacement lamps. Two brilliant lamps are available: long-life 'minicans' and vibration-resistant 'DYS'.

Both lamp systems (which are interchangable) position the filament at the focal point of an internal polished aluminium parabolic relector and the Joules stabilised bulletproof lens resists radiation browning.

The Joule's underwater electrical connector is the same system which was developed for teh rough-and-tumble offshore field. It is waterproof to 20,000 feet depth and armoured with delrin and aluminium. The Joule mounts on a stainless steel pan-and-tilt yoke, or is suspended with a suspension assembly.

Optional non-browning fused silica lens is also available, as are anti-backscatter blue and blue-frosted lenses.