ACME original 'silent' dog training whistle no. 535. Adjustable frequency. Instruction leaflet included. Made in the UK. Good sound quality. Weather-proof. Solid brass with nickel plated finish

High quality, clean sound. My dog responds playfully and with a sense of urgency.

No wonder this whistle has been around for 150+ years. Absolutely perfect training device. Easy to use and adjust. It is not silent, but I'm sure there are octaves that dogs hear through this unit as well as the pitch people can hear. Excellent buy.

i have an OLD Acme dog whistle that i've had since about 1985. It has been wonderful and still works great. I bought this "updated" version on the stated information that the new version is good up to two miles. IT IS NOT AUDIBLE UP TO TWO MILES AS ADVERTISED. I bought one but returned it because the sound was intermittent. I returned it and requested a replacement, thinking the first one may have been flawed. NOT SO. The replacement is also intermittent and dogs do not respond any further than 1/8 of a mile. I tested it with my sons two dogs. We had the dogs at 1/2 mile, clear line of sight. No response. Same thing at 1/4 mile. No response. Finally, at less than 1/8 mile they barely responded. If you need the distance, I cannot recommend this product. My dogs have responded to the old whistle up to 1/2 mile or more. My current dog who is well trained and responsive to the whistle also does not even perk her ears when she is a mile out. For short distances, this updated whistle may be fine. If you are looking for a long distance whistle as I was, this is not it. Acme used to make great whistles, this updated version is a huge disappointment for the price. Good luck.

I went with this whistle because I read a blog that reviewed a bunch of different dog whistles and picked this "silent" whistle as it's favorite. It said that, while not completely silent, most testers described the sound as a burst of air since it's supposed to operate on a frequency not detectible to humans.Either my husband and I are Jack Russel Terriers or that's a complete exaggeration.It sounds like a whistle. To me it's not super loud like a coaching whistle but I can definitely hear it just fine and according to my husband it's so loud that he figures yelling at the neighbor's dogs to stop barking would be less likely to give him a headache than this whistle.Furthermore - the dogs reacted to it for about a day ... tops! After that it became so ineffective that we went back to yelling at them. I'm sure this works great on some dogs and is probably more effective if they're your own dogs and you can actually train them with it in some way but since so many other people are asking about getting neighborhood dogs to stop barking - this isn't your savior.

First, if you think a dog whistle is a magic whistle that stops dogs from barking, don't buy this or any other dog whistle. If you do, there's a 92% chance that you'll illustrate your lack of general knowledge by giving it a one star rating because, "it didn't work," and returning it. There's an 8% chance you'll illustrate your lack of general knowledge because the dog in question is one of the random 8% of dogs that stop barking when distracted, and you give it five stars because, "it worked."So, if this is your line of thought, google dog whistle; Galton whistle; and; classical, Pavlovian, or, respondent, conditioning; before you order anything to quiet your neighbor's dog. Yes, there are sounds that dogs may find painful to hear, so the noise can be used as negative reinforcement for negative behavior, but a dog whistle is not likely to produce one of these sounds. A dog whistle is a signal that's used to condition dogs, just like a command. So, whistling at a dog and expecting it to just stop barking is as silly as saying, "Alto!," to a barking dog and wondering why the dog didn't just stop.That said, this is a very nice whistle. As other viewers have pointed out, it's not inaudible throughout its range of pitch. But, it's not supposed to be. A pitch that's inaudible to humans, but audible to a dog, is only useful for a fairly limited short distance. At greater distances, a pitch needs to be used that is audible to humans. The Acme's pitch is adjusted by screwing a sleeve in or out. It has four graduation marks on the side and a set screw to keep it at the desired pitch. The whistle is well made, and a chain keeps you from losing the cap.I scientifically tested the inaudible ranges on my cats, whose ears perked when I couldn't hear anything. I have very nerdy and scientific cats. I don't have a dog. Oddly enough, in spite of my preceding rant, I'm planning on using mine to quiet my farging icehole neighbor's dog.This dog barks at everything, including air, and an inaudible pitch. My neighbor's definition of too much barking and mine differ significantly. So, I plan on sitting quietly in my backyard for several weeks, silently whistling this stupid animal into a frenzy on a regular basis. My neighbor's anticipated response is to quiet the dog. My diabolical plan is to let my neighbor condition the dog to not bark at the whistle. Getting to annoy the crap out of my idiot neighbor in the process is gravy on the biscuits. Once the dog is conditioned to not bark at the whistle, he should stop barking when I whistle.See the difference between a magic whistle and classical conditioning?