The G23 is a 2-pin cap with 23mm spacing between pin centres. The cap is used with Biax CFLs, which are the two-legged, single-turn lamps used in various luminaires. Though they are generically known as ‘Biax’ (biaxial) lamps, these products are identified differently between manufacturers: Biax-S (GE), Lynx-S (Sylvania), Dulux-S (Osram), PL-S (Philips). The ‘S’ in this case refers to the single-turn design.
2-Pin Single Tube CFL (Biax).