Yes, the Centripetal Force Apparatus Moment of Inertia Accessory Kit (CFA-MIK) will fit on both the Centripetal Force Apparatus (CFA) and the Go Direct® Centripetal Force System (GDX-CFA).
When using this accessory with the Go Direct® Centripetal Force System (GDX-CFA) use a Go Direct® Force and Acceleration Sensor (GDX-FOR) to collection angular data. The sensor will rest on the clip that is on the shaft. Tighten the thumbscrew gently to force it to rotate with the shaft.

When using this accessory with the Centripetal Force Apparatus (CFA) use a Photogate (VPG-BTD) to collect angular velocity data as explained in the user manual.

When using the original CFA, the clearance between the photogate and horizontally mounted components of the Moment of Inertia Kit require you to  elevate the components on the shaft by ~3/8″. This can be accomplished by adding about 4 flat washers with 1/2″ diameter holes.

Go Direct Centripetal Force Apparatus, Troubleshooting and FAQs
How do I use the Moment of Inertia Kit with the original CFA?