Hello folks, can't remember if I already included this here. On many occasions I have need to make something mobile and yet the wheel locks on many casters aren't very user friendly or efficient. Here is a very inexpensive and effective design that might be an answer for some of you. This incorporates a single wheel, but, with a little bit of additional thought you could use 2 just as easily. Hope this makes sense and can be understood, it basically uses an offset sleeve to move the wheel up/down in a sliding tube configuration. Best regards, Allan