Because of them my heel rises / falls with every step. They're sharp where the show hits the heel. This causes my skin to wear down quickly and I start to bleed. I contacted Merrell and they did not offer support or allow returns/exchanges. I have a pair of Jungle Mocs the same size (13) as these and they fit great. I tried using inserts to fill in the empty space but that didn't work. The heels didn't help. Attaching soft tissue did not help. I'll just throw this in the trash. I don't want to cause anyone that pain by sacrificing it.