New Style Potty training pants
These are from a different supplier than the other training pants.
The cut is different – its is bigger over the bum area and the elastics are softer and have a lot more stretch to it. I would say the 80 is slightly bigger than the medium, the 90 is a little bigger than the large and the 100 is around te same size as the XL of the old Potty Training Pants
I would say the size will depend on how thin or chubby your little one is – thin ones (no matter the age will fit in the smaller sizes and very chubby little ones will fit in the larger ones.)
As an indication: the 80 and 90 fit my very skinny 14.8 kg 4 year old toddler but the 100 is way too big around the bum. All the elastics seal around his legs and waist but it gets bigger and bigger over the bum. None of the elastics were so tight that they made red marks, but please note he is tall and really very skinny.
From experience selling these the 80 will fit skinny toddlers up to about 15/16 kgs. The 90 can fit probably up to 18/19 kgs.
Because there is so much room for the bums, I would suggest the 100 only for very chubby little ones with fat little bums. The leg elastics are very stretchy, so bum size is the most important not so much the leg size.
Not all of the new potty training pants have pictures appliquéd on the bum.