These wireless lavalieres are powered by 2 AA batteries each. They automatically find the best frequency and will pair it up from the receiver to the transmitter. They work better than the Sennheiser EW's because they don't transmit loud scratches when they go out of range. Comes with two mic covers and four rechargeable AA-batteries. Here are other lavalier packages: 1X Sennheiser G3 (Lavalier) Tx/Rx ($19) - https://www.sharegrid.com/losangeles/l/85370?type=rent 2X Sennheiser G3/G2 (Lavalier) TX/Rx ($36) - https://www.sharegrid.com/losangeles/l/118489?type=rent 2X Sony UWP (Lavalier) Tx/Rx ($56) - https://www.sharegrid.com/losangeles/l/171159?type=rent Here are microphone sound mixers: H4n (2 channel) Mixer ($10) - https://www.sharegrid.com/losangeles/l/64208?type=rent H6 (4/6 channel) Mixer ($19) - https://www.sharegrid.com/losangeles/l/85204?type=rent F4 (4/6 channel) Mixer ($19) - https://www.sharegrid.com/losangeles/l/115994?type=rent Here are boom microphones: Audio Technica 897 Boom Mic (AA-Powered) & Pole ($19) - https://www.sharegrid.com/losangeles/l/64218?type=rent Audio Technica 4073a Boom Mic (Phantom Powered) & Pole ($29) - https://www.sharegrid.com/losangeles/l/64256?type=rent Microphone Accessories: Orca Sound Bag ($15) - https://www.sharegrid.com/losangeles/l/86996?type=rent Zeppelin Boom cover (wind protection) ($19) - https://www.sharegrid.com/losangeles/l/64227?type=rent Auray Boom Pole Holder (For C Stand) ($5) - https://www.sharegrid.com/losangeles/l/64579?type=rent Handheld Microphone: Shure SM57 ($10) - https://www.sharegrid.com/losangeles/l/82055?type=rent Go to 8:30 in this video to see how to sync/scan these lavaliers: https://www.youtube.com/watch?v=fkG_4uC8q9w