998e2bac_n_of_No_Pull_Dog_Training_Aids__2
[0] Pinch Collar or Prong Collar (Metal or Plastic) [1] Herm Sprenger Good Dog Collar [3] Dog doesn't generally mind having it put on. Effective at reducing pulling for most dogs. [4] Most brands are difficult to take on and off. Can cause irritation to the neck area. Can break apart. Can make sensitive, fearful or aggressive dogs more fearful or aggressive. [5] 2 out of 10 [2] 
When the dog pulls, points on the collar come together to pinch the skin on the neck causing discomfort and discouraging pulling.
Comparison of No-Pull Dog Training Aids
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