If you're ballasting your tires, regular monitoring of your tire pressure is essential. Slime's Air & Water Pencil Tire Gauge was designed specifically for ballast tires, and easily clips onto a pocket, so you'll always know where it is.

5-50 psi
Especially designed for tires with air and water inside
Great for tractors and other ballasted tires
Chrome gauge body
4-sided tongue measures psi, kPa and bar