SET Size Chart for Medium Breeds:

The three-piece set includes the following sizes:

Size S comes with a collar in size S, a harness in size S, and a matching leash.
The collar fits on a neck of 13.8 to 16.7 inch (35 - 42.5 cm). The harness fits a chest girth of 15.7 up to 28.7 inch (40 cm - 73 cm) and a lower neck circumference of 25 to 48 cm (9.8 - 18.9 inch).

Size M comes with a collar in size M, a harness in size M, and a matching leash.
The collar fits on a neck of 16.7 to 19.7 inch (42.5 cm - 50 cm). The harness fits a chest girth of 19.7 up to 29.5 inch (50 - 75 cm) and a lower neck circumference of 13.8 to 22.8 inch (35 - 58 cm).

Size L comes with a collar in size L, a harness in size L, and a matching leash.
The collar fits on a neck of 19.7 to 22.6 inch (50 - 57.5 cm). The harness fits a chest girth of 23.6 up to 45.3 inch (60 - 115 cm) and a lower neck circumference of 43 to 63.5 cm (17 - 25 inch).

Size XL comes with a collar in size XL, a harness in size XL, and a matching leash.
The collar fits on a neck of 22.6 to 25.6 inch (57.5 - 65 cm). The harness fits a chest girth of 37.4 up to 57 inch (95 - 145 cm) and a lower neck circumference of 21 to 33 inch (53 - 83.5 cm). 

Important: Please measure your dog accurately before placing an order. Ensure there’s a two-finger gap for a comfortable and secure fit.