Possible Clues:

• Water/gas supply valve
• Corrupt cop invested in fund that controls liquidity flow?
• Beastly types ringing piano firm for something to control flow from pipes
• Isolating valve in pipework
• Politically correct ring in stock is a turn off
• Standard lagging work besides cold tap
• Handled pipe to cut supply
• Short pipe that may be opened by turning a key or handle
• It controls the flow of fluid through a pipe
• Desist, male bird! it's a valve in a pipe