$SportDOG created the Pro Hunter SD-2525 for hunters and trainers alike. For hunters and trainers who want the best of both worlds, this is it! Ideal for hounds and other sporting breeds, once again SportDOG Brand delivers on our promise: Gear the way you'd design it. The new SportDOG ProHunter SD-2525 design meets updated technology in the SportDOG ProHunter 2525 2-DOG Training System. With a 2 mile range and expandable up to 6 dogs, this is the remote training system for demanding users such as professional trainers and hunting guides with long ranging beagles, hounds and pointers. The SD-2525 allows control of up to six dogs by adding SportDOG SDR-A or SDR-AH Add-A-Dog collars. The compact transmitter features color-coded indicators that correspond to available collar strap colors.