I recently purchased the Sears "Professional" Lithium batteried driver drills. I purchased two because I was in the process of erecting a metal building. The batteries and charger worked good but the keyless chuck on both drills exhibit what I call "Auto Loosen". I have several other keyless chucks in my shop and none of these exhibit the same characteristics. I called Sears Customer Service to complain and they told me to visit my local Sears dealer. The local Sears dealer told me to call Customer Service. Whoa!! I've been a victim of that before. I will now look for my tool requirements somewhere else.
Stu Fields