Acme whistles are great for close work and a different style of sound for a different command.
210 - High pitch, quiet to users, fitted with a weatherproof pea to provide the famous Acme trill of rolling notes or a variable frequency.
210.5 - High pitch, quiet to the user, preferred by Spaniel owners but an excellent all-round dog whistle for close and distance control.
This whistle is recommended for both use in Town and the Countryside .
211.5 - Medium high pitch, single note, preferred by Labrador and Retriever trainers; good distance whistle.