ACME Silent Whistle No. 535 - The 'Silent' Dog Whistle for All Breeds | Also for Animal Training with Dolphins | For Humans (Almost) Not Audible

PRECISION SILENT DOG WHISTLE DESIGN: The ACME 535 Silent Dog Whistle is designed as a focused training aid, producing a sound that is barely audible to humans while remaining clearly perceptible to dogs. Historically, whistles of this type have been used as part of structured training approaches where controlled sound cues are required, reflecting long-standing practices documented across generations of dog handling. ADJUSTABLE BRASS CONSTRUCTION: Crafted from solid brass, this adjustable acme dog whistle features a screw piston mechanism that allows precise tuning across a wide frequency range. Special air directors support controlled sound output, reflecting considered acoustic design used in dog training and across a long-standing range of dog whistles. CONTROLLED SOUND OUTPUT: Designed to support structured dog training, this dog training whistle allows handlers to introduce consistent sound cues with minimal effort. Its controlled acoustic profile supports use in varied environments and fits naturally within a practical kit of dog essentials. VERSATILE FOR EVERYDAY ROUTINES: Suitable for walks, training sessions, and outdoor activities, this whistle integrates easily into daily routines alongside trusted dog walking accessories. Supplied with a booklet providing clear guidance on adjustment and training use, it supports considered handling as part of a practical set of dog essentials. UNRIVALLED PERFORMANCE, ICONIC DESIGN: Established in the 19th century, ACME has spent generations refining the art of sound signalling. Working dog whistles sit alongside professional, sporting, and safety applications, with every design reflecting depth of knowledge shaped through long-standing practice and continuous development across a broad range of uses.