dogtra field star 1/2 mile collarthis product exceeded all my expectations. it works through concrete block buildings, it works from long distances, it has an adjustable shock intensity level, if a weak shock doesnt straighten my dog up then i give him a stronger shock till he acts right. my dog is a highly agressive large pitbull and this collar makes him sit up and act right faster than a prison guard with rubber slugs in a 12 guage. if u have an agressive hard to control dog , THIS PRODUCT is exactly what u need worth every penny. it is tough it survives being dropped , battery charges last a long time , and it is made with care out of high quality material ..this is not made in china cheap quality that falls apart after a few months of hard use..it works well through the test of time and a very active messy pitbull… ยป read more about Dogtra 1900NCP Field Star 1/2 mile Training Collar Single Dog
Ronnie Holt