I originally though it was a defective battery. After replacing it with your new battery the receiver charge light will not come on and when you plug in the charge cable it does not disconnect from the remote. I notice that a Large coil inside the receiver is defective. I had to purchase another receiver and I find that the ET-400 is not very good quality since the collar is only 1 year old. One star for ET-400

Old Battery would not hold a charge anymore. Battery came fast and was simple to change out. Extends the life of the ecollar.

Batteries worked for remotes and receivers no problem. The originals lasted about 6 yrs so hoping I can get a few years out of these replacements. Ordering and shipping easy although takes a bit to get across the country but I just did regular shipping. Thank you

E-Collar Technologies Li-PO Replacement Battery

Very easy to replace. 5 year old battery was not holding charge for long. Very inexpensive fix to completely renew our collar. Thx.