I've picked one up from costco around 4-5 years ago and paid the same 23-24$ back then, I expected it to go down in price, but to comment on this product it's far by the best product to send your kid to camp with, to ease all the shleping with all their water and nosh box with their hat box or what ever other stuff they had.
And if you want for $21 and fs choose the 3rd party. (decent ratings for the 3rd party seller.)
