Just got them yesterday and they seem ok, the collar dose tend to loosen up so I stitched my to fixed positions for each of my dogs and haven’t had a issue, I have a Large pit bull and a 4 month old German Shepherd and a black lab and they work great for all of them, each Chanel has memory of its own so the sensitivity can be different for each dog collar! 
these are great so far, my pup hears the audible and immediately comes to me, haven't had to vibrate or shock him and the light is great at night, helps us see exactly where he is.
Great has helped stopped the digging very useful good product
Absolutely LOVE!!! Compared to the one's I got from Amazon, sooo much better! (I showed a comparison pic) These are lightweight, the prongs arent metal, IT HAS A LOOP FOR A LEASH (amazon ones didnt even have that, was super excited about that), the remote is more compact (option for a string to hold it), it has all 3 channels, you can charge 2 collars at once. This remote is so mych easier to control as well, the other one I had to try to figure it out. This one is self explanatory. The ones from Amazon were so bulky and it made me feel bad to even have them wear them, my 3 dogs fit these new ones so well, and they havent even broke them off (the Amazon ones they broke off, chewed, etc) It came with extra pieces for the collars and remote just in case. They're waterproof! I havent tested the range yet, but all in all, I love them a lot! and for $33, I got a steal for 3 collars.
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