COLLAR 
Width: 2.5cm
S - 25cm - 35cm
M - 33cm - 43cm
L - 40cm - 50cm
XL - 47cm - 57cm
 
LEAD
Width: 2.5cm
Length: 1.2m
 
HARNESS - CHEST MEASUREMENT
Width: 2.5cm
S - 45cm - 60cm
M - 55cm - 70cm
L - 65cm - 85cm
 
If choosing between two sizes go for the larger size.