no offence intended here gents, but i cant believe the amount of people who havent seen/used one whilst out!
Very uselful tool, for various reasons as others have said, finding tube, listening to dog, etc etc.
Dog in, wait for it to settle, find a mark, drop bar in (obvioulsy gently as your breaking into tube) and listen to see whats happening. sometimes if your quarry is not quite bottled up, the noise of you barring etc will move them on tighter (or move althogether), saves you starting to dig and getting to say 18", only for ypur quarry to move say a foot or two and you having to s