The built-in wireless receiver allows you to use a dry body pack transmitter for class instruction, lecturing, making announcements, or multimedia presentations. Smart 300 covers all of your wireless needs plus additional audio inputs to add the most popular personal MP3 players on the market. Optional travel bag and tripod stand. Transmitter and Headset were designed for low activity upgrades below for ‘Fitness Level’ options. System not intended for in water use or splash proof water damage is not covered under warranty.