What is the difference between XDR and HG freehub?

XDR is SRAM's road freehub standard, 1.85 mm wider than Shimano's HG. XDR is required for SRAM 11/12-speed road cassettes (Force, Red, Rival AXS). They are not interchangeable.

Does this include the freehub body or just the end cap?

This is the end cap only — the non-drive-side axle retention piece. It does not include the freehub body or cassette interface.

Zipp

Zipp End Cap Rear ZR1 12x142 XDR 11-Speed

Name: Zipp End Cap Rear ZR1 12x142 XDR 11-Speed
Brand: Zipp
SKU: CMB_LONGSHINE_11.2018.064.005
Price: 4690.00 INR
Availability: InStock
Author: InstaSport Editorial

₹4690.00

Description

The Zipp End Cap Rear ZR1 12x142 XDR 11-Speed is a genuine replacement or conversion end cap for Zipp ZR1 rear hubs on 12x142 mm thru-axle road or gravel frames. It enables the XDR freehub body interface required for SRAM 11-speed and 12-speed road groupsets. Brand and model match is mandatory — thi