S: 46x38cm Suitable for pets under 0-2.5kg
M: 55x50cm Suitable for pets under 2.5-5kg
L: 63x53cm Suitable for pets under 5-7.5kg
XL: 70x60cm Suitable for pets under 7.5-11kg
2XL: 90x65cm Suitable for pets under 11-17.5kg
3XL: 100x75cm Suitable for pets under 17.5-25kg
4XL: 115x85cm Suitable for pets under 25-40kg
5XL: 125x95cm Suitable for pets under 40-60kg
**If your dog Length 50cm, then you should buy M or L