The AR51A-08 from AccuBeat is a Time and Frequency Standard with Frequency 10 MHz, Frequency Stability ±0.3 ppb, Output Power 10 dBm, Phase Noise -152 to -83 dBc /Hz, Short Term Stability 0.003 to 0.03 ppb. Tags: Time & Frequency Standard. More details for AR51A-08 can be seen below.