This 28T-48T 20DP Double Gear is used for the:
MK3 Swerve Module with the Fast ratio (in conjunction with the 16T hex gear).
This Fast ratio also requires a 16T pinion gear on the drive motor.
MK4 Swerve Modules with the L4 gear ratio (in conjunction with the 16T hex gear).
This L4 ratio also requires a 16T pinion gear on the drive motor.