The Acme 211.5 is the standard whistle for Retriever and Labrador handlers. Its medium-high tone carries well across open ground and gives clear, consistent commands at distance — exactly what you need when your dog is out on a long mark or a blind retrieve. Frequency-standardised, so a replacement will always sound the same to your dog. The most widely used whistle in gundog training for good reason. Pairs perfectly with the Byron Gundogs Lanyard.