The professional's choice: This special whistle holds its frequency no matter how loud you blow. Less confusing for your dog, especially over distance or with multiple users. Blow soft for close work or blow hard for a louder sound over greater distances, the frequency stays the same. A great all-rounder: An excellent whistle for harder to train dogs, disobedient dogs, hard of hearing dogs, and heavy cover situations. Works very well with Pointers, Setters, Retrievers, Labradors, and most Terriers. Lightweight, small and durable: Made from BPA Free plastic to food grade standard in a choice of colors. Pealess/no cork/ball free. Medium Pitch. 110dBA. Weight: 3.5oz / 4g. Measures: 2.4 inches/ 6cm x 0.6 inches / 1.5cm Emits a sound that is well within human hearing and loud, but not obnoxiously so. Easily heard over wind noise in open fields. Genuine ACME Whistle made in the UK by specialists with over 150 years of experience. Genuine original ACME Pro Trailler Gun Dog Whistle No. 212 Durable BPA Free Plastic to Food Grade Standard. Pealess/no cork/ball free. Medium Pitch. 110dBA. Weight: 3.5oz / 4g. Measures: 2.4 inches/ 6cm x 0.6 inches / 1.5cm Lightweight and small, the ACME Pro Trailler Gun Dog Whistle is a great all-rounder with a sound that is well within human hearing and loud, but not obnoxiously so. Easily heard over wind noise in open fields. This special whistle holds its frequency no matter how loud you blow. Your dog will always know it’s their whistle. This produces less confusion for your dog, especially over distance or if you blow hard when your dog becomes disobedient or goes off course during a Trial. Especially good over distance and works very well with Pointers, Setters, Retrievers, Labradors, and most Terriers. An excellent whistle for harder to train dogs, hard of hearing dogs, and heavy cover situations. The ACME Pro Trailler Gun Dog Whistle provides a constant frequency. No matter how hard or soft you blow the frequency remains constant. Blow soft for close work. Blow hard for a louder sound over greater distances. Hearing the same sound makes this easier on the dog and means your dog will know their call no matter who is working with them. When using a whistle as a training marker, instead of a clicker, it’s important that the sound remains constant. You want your dog to associate the sound of the whistle with the action you are training your dog to perform – and hearing the same sound makes this easier. The professional's choice, this special whistle holds its frequency no matter how loud you blow. A genuine ACME whistle designed and made in the UK by specialists with 150 years of experience.