dude, i really liked the locking mechanism when i checked it out at home depot. Then I ordered here. The first job I had, an electrician, was waiting for me because I completed it and used it as a plumb bob to determine where to put the lights across the table. I actually had to run to my truck and get another tape measure because the lock wasn't strong enough to support the weight of the tape itself! LAME! the ability to block it. I remembered. SUPER LAMB! I put it in a box with other tools after a long day of trying to use it. Have tried it a few more times since then on a few small jobs but it's just more effort than it's worth. from my house for a full refund.