Quantic PMI Model PDRO-6800M-13DBM-SFF is a Dielectric Resonator Oscillators (DRO) with an output frequency of 6800 MHz and a minimum output level of +13 dBm and has a reference frequency of 0.1 GHz, an input level of 3 to 13 dBm, an output level of 15.1 dBm, spurious of 89.5 dBc, and harmonics of 30.6 dBc. This model size is 2.25" x 2.25" x 0.62" and has SMA female connectors.   https://www.quanticpmi.com/product-details/pdro-6800m-13dbm-sff