Seatpost sizing has more increments than most riders realise, and a slightly wrong diameter either won't clamp or won't go in at all. This gauge reads the seat tube's inside diameter in one go.

Highlights

  • Covers 24 common seatpost sizes from 25mm to 34.9mm
  • Durable precision-cut acrylic
  • Insert into the seat tube until it fits snugly — no batteries, no guesswork
  • Compact and lightweight for the bench or a trailside kit

Sizes read

25.0, 25.4, 25.6, 25.8, 26.0, 26.2, 26.4, 26.8, 27.0, 27.2, 27.4, 28.2, 28.6, 28.8, 29.2, 29.4, 30.0, 30.2, 30.4, 30.8, 30.9, 31.4, 31.6, 31.8 and 34.9mm.

Compatibility & fit

Measures the seat tube's inside diameter directly — use the reading to confirm or shop for the matching seatpost diameter.

Wheels Manufacturing backs this product with a 1-year warranty against manufacturing defects from the date of purchase, and accepts returns of unused, unopened stock within 30 days of purchase. For warranty support, return the product to Tune Cycles and we’ll manage the claim with Wheels Manufacturing’s Australian distributor.

  • Reads 24 seat tube inside diameters, 25mm to 34.9mm
  • Precision-cut acrylic
  • No batteries, insert-and-read use
  • Compact enough for a toolbox or trail kit
MeasuresSeat tube inside diameter
Range25mm to 34.9mm (24 common sizes)
MaterialPrecision-cut acrylic
SKU SCV-WMTL-SP-GAUGE-1
Brand Wheels MFG
Shipping Weight 0.0670kg
Shipping Width 0.100m
Shipping Height 0.080m
Shipping Length 0.500m