How to identify your freehub body
Quick answer
The fastest way is by your groupset: Shimano/SRAM 8–11-speed uses an HG body; SRAM Eagle MTB uses XD; SRAM AXS road/gravel uses XDR; Shimano 12-speed MTB uses Micro Spline; Campagnolo uses its own body (N3W on 13-speed Ekar). Visually, an HG body has splines and a separate lockring, while XD/XDR are smooth threaded drivers with no lockring.
Drivetrain → freehub body
Find your bike’s groupset to get the freehub body the cassette mounts on:
| Your drivetrain / groupset | Freehub body you need |
|---|---|
| Shimano 8/9/10/11-speed HyperGlide (MTB & most road) | Shimano/SRAM HG (HyperGlide) |
| Shimano 11-speed road body (1.85 mm longer) | Shimano HG 11-speed road |
| Shimano 12-speed MTB (XTR / XT / SLX / Deore) | Shimano Micro Spline |
| SRAM 11/12-speed MTB (Eagle: GX / X01 / XX1) | SRAM XD Driver Body |
| SRAM 12-speed road & gravel (Rival / Force / Red AXS) | SRAM XDR Driver Body |
| Campagnolo 9–12-speed | Campagnolo |
| Campagnolo Ekar 13-speed | Campagnolo N3W |
Telling them apart by eye
- Shimano/SRAM HG: stepped splines of different heights plus a threaded lockring that holds the cassette on.
- SRAM XD / XDR: a smooth threaded driver with no lockring; the cassette threads straight on. XDR is 1.85 mm longer than XD.
- Shimano Micro Spline: 23 fine, evenly spaced splines — narrower than HG — used by Shimano 12-speed MTB.
- Campagnolo: distinctive deep splines; N3W is a shorter spline used by 13-speed Ekar (an adapter fits older Campagnolo cassettes).
Frequently asked questions
Check your groupset first — it determines the body. If you’re unsure, look at the driver: a lockring and stepped splines means HG; a smooth threaded driver with no lockring means SRAM XD or XDR; fine even splines means Shimano Micro Spline.
HG is the most common body, used by Shimano and SRAM 8- to 11-speed cassettes. It has splines of varying height and a threaded lockring. Shimano’s 11-speed road body is 1.85 mm longer than the MTB HG body.
Both are smooth threaded SRAM drivers with no lockring. XDR is 1.85 mm longer than XD. XD is used by SRAM Eagle MTB; XDR by SRAM AXS road and gravel. See the XD vs XDR guide for cross-compatibility.
Micro Spline is Shimano’s 12-speed MTB body (XTR, XT, SLX, Deore 12-speed). It has finer splines than HG and allows a 10-tooth smallest cog. It is not interchangeable with HG or XD.
Campagnolo bodies have a distinctive deep-spline pattern unique to Campagnolo cassettes. The newer N3W body is shorter and takes 13-speed Ekar, with an adapter available for older 9–12-speed Campagnolo cassettes.