Herm Sprenger Stainless Steel Ultra Plus Training Collar features the centre plate configuration pioneered by the outstanding neck tech prong collars. This striking symetrical design offers benefits that are both functional and aethetic with the confidence that it has been developed by the leading manufacturer of quality dog training products. Top quality training aid used by the pros worldwide. Most common collar for average sized GSD is the 3.25mm.

3.25mm - 23 inches - dogs between 45 lbs and 90 lbs

2.25mm - 16 inches - dogs under 40 lbs

4,0mm - 25 inches - dogs over 90 lbs