The rugged, all-metal design is comfortable for performers and presenters to wear for daily use on stage. It provides up to 8 hours of operation on two AA batteries, with a fixed 30mW RF power output and a transmission range up to 330 feet. The SK 100 G4 features a locking 3.5mm connector with an adjustable input level to accommodate the compatible lavalier or headset microphone of your choice, or an adapter cable for guitar and bass. When the Sync function on the receiver is engaged, the transmitter and receiver quickly link to the same frequency via infrared. The transmitter's backlit LCD displays essential information, while the convenient programmable mute function can be locked out to prevent accidental changes during a performance. The unit can also be powered by a single rechargeable BA 2015 Accupack battery (available separately). Side contacts allow for recharging the Accupack without removing it from the transmitter—requires the L 2015 quick-charging unit (available separately). The SK 100 G4 is backward-compatible with all previous evolution systems. You can mix and match G4/G3/G2/G1 receivers or bodypack, handheld, and plug-on transmitters. It is also compatible with EW 300/500 systems.