The Dogtra brand makes a lot of training equipment for sporting dogs. They have one dog fence system called the, the EF-3000 Gold. The Dogtra is the only rechargeable in-ground system that allows you have independent correction levels for each dog, so is a good choice if your dogs are of pretty different temperament or size.
Box Contents
The Dogtra collar is a little on the chunky side and looks dated but does the job. Avoid using this on dogs over 20 lbs. The collar has been updated from the previous version to use a lithium polymer battery. It has a much better life span than the nickel metal hydride battery it replaces. We find these get you 3-4 weeks of charge and take two hours to recharge.The collar has five correction levels, and vibrates as well as beeps to warn the dog that they are too close to the boundary before giving the dog the correction. The vibration feature is great for older dogs that are hard of hearing. The correction levels are set on the collar which lets you set an custom correction level for each dog on the system. The collar comes with long and short probes and these plastic no shock training probes.
Transmitter
The transmitter on the Dogtra can do up to 40 acres. It has the basic controls - an on/off switch and a boundary width dial. There are two wire ports for the boundary wire loop. And a third wire port for you to ground it directly if there is a grounding stake nearby. Don't worry if there isn't, you can use one of the optional lightning protection modules to ground the wire using the ground connection in any three prong power socket. The system comes with the standard 500 feet of18 gauge boundary wire,50 flags and two waterproof splices.
Conclusion
This is a good system. But at this price point, I think the Innotek 4100 has it beat. The collar on the Dogtra is significantly bigger and the Dogtra doesn't have the features like the battery backup, collar fit and the indoor / outdoor pods.
There are a few situations where it has the Innotek beat. First if your dogs can't hear very well, the vibrate feature here is really useful. Second, if your dogs are very different sizes the ability to set the correction level for each dog independently on the collar make this a better choice. Third, if you need more than the 25 acres capacity on the Innotek, the 40 acre capacity on this unit make this the one to get.