Included are a combination of lavs if desired, however, I do have four matching Sennheiser lavaliers, so that could be the go-to option for which brands to choose from. My recommendation when using the G3 Sennheiser is to first go into the menu of the receiving unit, then Easy Scan Setup, then New Scan. Let it find a few clear channels. (Takes a min or two). Once it has found it's bank of channels, you can set g2 first to one of these channels. To sync the G2, simply read what the G3 says is a clear channel. On each G2, press menu, select Tune, then hold the up or down button until reaching the desired frequency on both units. Once you have found a clear frequency on the g3, press on/off to get out of the Easy Scan Setup Menu, and then navigate through the main menu to Sync. Press Select and then hold both transmitter and receiver's infrared light side by side like they are kissing. Then they will be synced. (It’s the little dark plastic cover) hold those side by side.