Super strong and stylish dog whistle and clicker neck lanyards are available here:  
DogCatz No-Frills Dog Whistle, Training Puppy, Cat  Obedience 
Recall, Stop Barking, Loud - Not Silent
 

* Very High Pitch    
 * Train to sit, come, stand, lie down and many more
      * Designed for Dog Training, start them off when puppies
           * Associate the whistle with good behavior and rewards/treats
      * Can save your dog's life when in danger, ie running toward a busy road
      * Call your dog in from outside
      * Encourages interaction and play between dog and owner
      * Train your dog, puppy to be well-behaved

This Dog Training Whistle is strong and durable, designed to encourage interaction between owner and pet for a number of reasons; play, obedience training, tricks (sit, come, stand, lie-down, etc), safety from dangers and traffic.  Please note, this is not a silent whistle, a high pitch sound does omit when blown.