The G24Q comes in three different forms: G24Q-1, G24Q-2, and G24Q-3. Each of these has an arrangement of 4 pins with 24mm spacing between centres, but their outer plastic guides are set at different positions and they are therefore not interchangeable. These caps are used on Double and Triple Biax CFLs for applications such as ceiling lights, wall lights, and table lamps.
G24Q-1, G24Q-2, G24Q-3.
4-Pin Double Tube CFL (Double Biax), 4-Pin Triple Tube CFL (Triple Biax).