i got to lookin at proto and mac tool boxes and i saw that they were quite the same, check out these pics, the dimensions are the same, the shape, the lock position, only major difference are the casters, and the fact that proto and mac are both owned by stanley works
http://i156.photobucket.com/albums/t29/wesreams42/proto.jpg $2,900
http://i156.photobucket.com/albums/t29/wesreams42/mac.jpg $7,600
http://i156.photobucket.com/albums/t29/wesreams42/proto.jpg $2,900
http://i156.photobucket.com/albums/t29/wesreams42/mac.jpg $7,600