There are two main problems with a typical marking gauge: you have to tilt it just right to avoid pin chatter, and the pin tends to follow the wood grain, throwing off your line. The Veritas wheel marking gauges solve both problems.
The hardened steel wheel cutter scribes perfectly at any point of its circumference. Since it cuts wood fibers rather than tears, it marks cleanly, even on cross grain. The wheel's single-sided bevel provides accuracy by pulling the gauge face against the stock. Its cutting edge is at the extreme end of the rod, useful for transferring dimensions such as tenon shoulder and mortise depth.
The wheel retracts into the face of the gauge for storage and protection. The gauges are very easy to set thanks to the internal O-ring to keep light but constant friction on the rod.
Hardened steel wheel with single-sided bevel pulls gauge face against stock, maintaining accuracy
Cuts wood fibers - does not tear
Marks cleanly, even on cross grain
The wheel retracts into the face of the gauge for storage and protection