I have 2, and highly recommend this great product. Anyone painting on canvas should have them. Its a simple idea with a funny name and a reasonable price. It makes "schlepping" a wet canvas so much easier. With 2 you can carry 2 paintings back to back.
Note that the recipe on some bottles (1 tsp in 1 pint cold water) makes a too-thin solution. Better to follow the online recipe from Lineco: 1 rounded tablespoon in a 1/2 cup water and then thin to the consistency you want once it gels.