Both 10mg. I am pretty sure there must be some because ever since my doctor told me to move from the SR version to the LA I have experienced severe confusion. It took me 4 years to realize it was Ritalin LA that had been causing me those symptoms. It took me that long to find out because I had assumed that because Ritalin SR had worked for me, so would Ritalin LA. But I was wrong. I spent years changing time antidepressants, taking different mood stabilizers, anxiety pills and antipsycothic drugs trying to control what was actually being caused by Ritalin LA. I know for sure now that it was the LA because I recently moved back to the SR one and all my confusion symptoms have completely disappeared. I am still curious though as to the existence of any difference between both drugs. Could anyone help me?