Basics:
GS=Gap Short (shortened electrode space)
DE=Double Ended (double-sided lamp with threaded pin)
SE=Single Ended (one-sided lamp)
PAR=Lamp built in a parabolic reflector
HMP=Due to their special filling and to their electrode system, HMP-lamps cannot only be "dimmed", but also be "boosted", i. e. be operated beyond their rated power. During this, the light technical characteristics, such as color temperature, color rendering index and light output are practically constant during "dimming" and "boosting".