Using a revolutionary new non-linear gauge scale technology, the Silca Terra pump uses custom gauge internals to create a gauge which allows for 0.5psi precision at the low end of the range climbing to 2psi precision at the high end of the range (120psi). This unique design allows for a gauge with 120psi overall capability, yet 50% of the gauge face contains 0-30psi (0-2.1bar).