Pin-based low energy bulbs. These lamps have 2 or 4 electric pins with plastic support clips at the center in various layouts depending on the wattage of the bulb.
Each manufacturer has their own brand name for this type of bulb:
Kosnic : Exun
GE : Biax T/E
Osram : Dulux T/E
Philips : Master PL-T
Sylvania : Lynx-TE