Related Clues:

• Listen in, in a way
• Keg add-on
• Snooping aid
• Beer barrel poker?
• Anxious foot action
• Plant a bug
• Furtive listening device
• "This is Spinal ___"
• Begin to use
• Surveillance option
• Audible dance style
• FBI device
• Rap lightly
• Beer keg feature
• Intercepting device