Every pooch needs a Queen B Country genuine cowhide and leather collar. Genuine cowhide top with a leather back and quality brass hardware. Measurements taken from first to last hole. Extra Small - 16cm - 26cm Small 25cm - 35cm Medium 36cm - 46cm Large 47cm - 57cm Extra Large 58cm - 68cm (Extra Small & Small are 2.5cm, Medium, Large and Extra Large are 3cm wide)