Gamebird Olive Barley Twist Whistle Set 211.5 Acme whistle (very high pitch) Twisted rope loop for safekeeping Suitable for training dogs Consistent noise Gamebird Olive Barley Twist Whistle Set uses an olive coloured twisted rope loop making it easier to keep the whistle at hand during extended periods of time. The whistle itself is a 211.5 Acme whistle which is known for a very high pitched noise which is bound to grab your dogs attention.