The duo covers pop, rock and country music focusing on old classics with an occasional contemporary artist  mixed in.   They use no pre-recorded tracks, although Erol has a specially modified guitar that enables it to sound like other instruments, while Lisa plays percussion to keep the groove hoppin!  Vocal harmony is the sweet spot for the SommerTime Duo!   Lisa and Erol can also be seen performing together in the band IMAGES.  Lisa ocassionally also makes an appearance with Erol in the Sommer & Klann band, she can also be seen performing regularly as the Sweet Green Apple in the well known Cleveland group The Pop Tarts!