This Sonic collar provides a distraction for small younger dogs. Microphone-activated with low and high settings, this unit deters barking via a loud, audible sonic tone.
Features and benefits: 
Lightweight receiver collar with nylon collar strap

Microphone-activated

Uses sonic sound to deter barking

High/low sensitivity settings
System includes: 
Nylon Collar Strap and bark control unit

6-Volt Lithium Battery (RFA-67D-11)

Instruction Manual