Yes my arm is turning early. I always thought it was my wrist but after watching video my whole arm is turning early. I hate to put a wrist brace on but I just can't stop turning my arm/wrist early. Need to stay behind the ball and stop coming over the top. Looking for a wrist device (if there even is one) to help me stay behind the ball.    Thanks 

To a bunch of guys who have never tried the Robby Restrictor.....you all are knowing and to that I say "WHATEVER"!  You gentlemen are the residence "EXPERTS".  What do I know.  I am a poor bowling mortal who tried it and for me it worked.
I guess I should feel grateful that I didn't have to hire a expensive coach to solve the problem.  Man am I lucky guy.
Sorry OP you will have to hire a coach. I still wish you well in resolving your stated problem. 

+1  ^^^^^

Turning the arm early can also be caused by late timing.  You may subconsciously pull the ball through the bottom of the swing and roll the arm/wrist over.

A good coach can will see if this is the case immediately, but a possible quick fix is to experiment with a shorter or earlier pushaway and see if it's easier to not 'roll over'.

Hope it works out...