The new generation of the popular "Roger Beep".
The RB2 has many new features over the older models. Take a look at the feature list below.

Metal Mounting Bracket
On-Board Talk Back Resistor
Front Side or Back Side Beep
Switch Jumpers for Switchable RB & TB On/Off
Adjustable Beep Tone (Full Range Tuning)
High Quality Durable Fiberglass PC Board
Socketed IC Chip for Easy Repair (If Ever Needed)
Extra Relay Contacts for Other Use

Info sheet
Install sheet