Aetertek GT-211SW dog training shock collar for little, small and medium dog. Collar features 3 levels of sounds, 3 levels of vibration and 10 levels of shocks. Transmitter and receiver are rechargeable and has a 400 yard long range. Strap can be adjusted from 2" to 9" long which will fit and work with dogs from 6 lbs to 50 lbs. Receiver is water-resistant. Use this collar for basic training, digging, barking, jumping on people and other training needs. Package contents: 1 rechargeable transmitter, 1 rechargeable water-resistant receiver, 1 strap adjustable from 2" to 9" long, 1 charger, 2 sets of metal prongs, 1 user manual.