The player delivers 40 hours of playback on two AA batteries (not included) bolstered by Sony's two-position automatic volume limiter system (AVLS), which conserves batteries and guards hearing by capping listening level. Eight playback modes include shuffle, program play, and repeat play, and handy bookmark playback lets you program favorite songs from multiple CDs and play them back at the touch of a button. Other features include a heat-resistant lid for durable outdoor use, audio CD-R/CD-RW playback, and Digital Mega Bass sound for heavy-duty low-end reinforcement.