Baby walker extension

I got this walker: http://www.target.com/p/cosco-seaside-friends-infant-walker-whale/-/A-14590976#prodSlot=medium_1_1&term=baby+walker and found that even on the lowest setting, baby's legs didn't reach the floor.
Apart from whether you should use one of these (I learned from this article, discouraging any use of walkers, that you can go to jail for possessing a baby walker in Canada: http://consults.blogs.nytimes.com/2010/02/22/the-dangers-of-baby-walkers/?_php=true&_type=blogs&_r=0 ) these inserts snap into the channels and allow the careful parent to set the walker a bit lower than normally allowed.