Tacx SRAM XD-R Direct Drive Freehub - Body for Type 2 Axles,

Type 1 Axle
6 mm or 9 mm internal diameter axle hole suitable for a quick-release skewer. Adapters allow for a thru-axle bike to be installed onto the trainer using a quick-release skewer.

Type 2 Axle
12 mm internal diameter axle hole suitable for using a bike's thru-axle. Adapters allow the use of a quick-release skewer as well.

How Do I Determine Which Type of Axle My Trainer Has?

Type 1 trainers:

• NEO Smart
• NEO 2 Smart
• FLUX Smart
• FLUX S Smart*
• FLUX 2 Smart*

Type 2 trainers:

• NEO 2T
• NEO 2, Type 2
• FLUX S Smart*
• FLUX 2 Smart*

*NEO 2, FLUX S and FLUX 2 trainers have been manufactured using both Type 1 and Type 2 axles. You can choose one of the following identification methods to determine which axle type your trainer has:

• Identify the part number on the cassette body installed on the trainer out of the box: Shimano Freehub bodies:
  Type 1, T2805.01 (S)
  Type 2, T2875-01
• Observe the perimeter surface of the axle endcaps on the trainer, looking for any white letters / numbers identifying the appropriate side for installation and axle diameter x length:
  Type 1: All black endcap, Quick-release compared to thru-axle: no letters or numbers printed on either cap
  Type 2: Quick release caps will be labelled: "QR DS", "QR x 130 NDS" or "QR x 135 NDS". Thru-axle endcaps will be labelled: "12 DS", "12 x 142 NDS" or "12 x 148 NDS"
• Measure the inside diameter of the trainer axle with the cassette body removed using a caliper tool
  Type 1: 6mm or 9mm
  Type 2: 12mm