You’ve probably seen those cloth neck coolers for bipeds and I bought one for my dog last year but of course it would not stay on: you have to tie it like a scarf and with one swoop of his paw my dog could strip if off faster than the Gentle Leader. The people variety is also pretty bulky and heavy when filled. This Cool Collar looks like a good alternative since it has a built-in clasp and comes in three sizes: yip, Bark, and WOLF. From $7-$10.
Via 7Gadgets