IMPORTANT: The adjacent MK4n Swerve Modules on a typical drivetrain are mirrored from each other, and there are consequently two kit layouts: "A" and "B". Scroll down to review how they are ordered, as well as ensuring you receive the correct encoder configuration.
New for spring 2024, the MK4n Swerve Module leverages the proven MK4i architecture into a new form factor. With the narrow side being only 4" wide inside of the frame member, it helps enable:
Wide game piece intakes between the swerve modules.
Compact drivetrains (accommodates a flat mounted FRC battery in an 17.5" wide drivetrain).
Additional functional differences as compared to the MK4i include:
Beyond supporting 0.25" magnet encoders it also supports 0.5" hex encoders. The hex encoder utilizes this Center Column. 
16T drive and steering pinion gears for faster drive and steering speeds.
10-32 threaded holes in the motor plate for covers to be added.
Please note:
The NEO Vortex kit works for the NEO Vortex motors with the 8mm keyed shaft.
The Falcon 500 kit is primarily for the Falcon 500 motor. It can also work for the NEO Vortex motor with the Falcon spline shaft, but the shaft spacers are not included (they are supplied with the Falcon motors), and the Semicircle Spacer kit is also needed.
Like the MK4i Swerve Module, the MK4n incorporates:
On-axis steering encoder (not included). Zero backlash, and the module can be disassembled/reassembled without resetting encoder offset
All plates made out of 7075-T6 aluminum
All steel gears
Includes secondary plate to box in frame
10-32 mounting holes on main plate for subsystems (e.g., collector)
Encoder guard to protect the CANcoder (or equivalent) steering encoder
Same frame-to-floor height as the MK4 and MK4i Swerve Modules
Same L1 - L3 drive ratios as the MK4i Swerve Module equipped with the 16T Drive Pinion Gear Adapter Kit
No 3D printed parts
Includes wheel tread cut-to-length, drilled, and pre-installed on the Billet Wheel option
Includes all hardware, including hardware to mount module to robot
The MK4n Swerve Module has many parts in common with the MK4i Swerve Module, and the conversion kit is available.
CIM motors are not compatible with the MK4n due to their larger diameter.
Because the MK4n Swerve Module does not have a symmetric footprint, a mirrored layout is required. The two layouts are known as "A" and "B". 
The module readily mounts to common 2" x 1" frame member material.