The UM-1 Crystals from MtronPTI is a RF Quartz Crystal with Frequency 6 to 200 MHz, Frequency Stability ±35 ppm, Frequency Tolerance ±25 ppm, Drive Power Level 1 to 10 µW, Load Capacitance 18 pF. Tags: Drop In. More details for UM-1 Crystals can be seen below.