With the current selection 5 products are available

BT12

2-Way Speaker Selector Switch

Designed to allow the use of two pairs of speakers with one amplifier
BT913

Premium 4 - Way Speaker Selector Switch

Designed to allow the use of 4 pairs of speakers with 1 amplifier
BT25

3-Way Audio Video Input Control

Designed to connect up to three audio video devices to two outputs such as
a TV and HI-FI
BT26

Phono / Microphone Pre-Amplifier

Designed for use with any amplifier without a phono aux input
BT928

Stereo Headphone Amplifier

Designed for use as a stand-alone unit
for personal listening