These are conventional metal halide lamps which are unusual as they are available in standard screw 27mm base rather than the large 40mm screw base.

This makes them very useful in small floodlights and signage and feature lighting around buildings.

Also known as HQI T, MHN T, HSI Tand HIE dependent on manufacturer.

There are two types, one which can be used in open lightfittings the other must be behind glass for safety.