The ATSM-49-R Series from MtronPTI is a RF Quartz Crystal with Frequency 3.579545 to 72 MHz, Frequency Stability ±50 ppm, Frequency Tolerance ±30 ppm, Drive Power Level 25 to 500 µW, Load Capacitance 18 pF. Tags: Surface Mount. More details for ATSM-49-R Series can be seen below.