I have a torso erector /sit up mechanism up for sale. It is a little larger than others I've seen. It uses a 2" bore x 4" stroke cylinder . 120VAC solenoid ,requires a minimum of 20 psi to operate. The overall length ,from the end of the pivot arm to the end of the base it is 38 1/2". 12" wide ,6" tall when lowered,34 1/2" tall when raised. The base is 27" long. It is made from 11 gauge 1 1/2' x 1 1/2' square tube . All of the bolts are 1/2" diameter as is the cylinder rod and rod end. If the arm is too long for you and you're interested in buying this I will cut it down to your specs ,reweld the end plate ,and repaint at no cost to you. This can be mounted on the ceiling, on a wall, in a coffin,all kinds of places. It will lift 20lbs. without a problem. There are speed control mufflers on the solenoid and a flow control valve on the extend side of the cylinder. This was added because when the arm was lowering, cylinder extending, it was hitting pretty hard even @ 20 psi. I wasn't happy with that so I added the flow control valve. It can easily be removed if desired and you won't need to add any tubing if you do that. I have it set up to use either a controller or a remote trigger or you can use a manual trigger. Instructions will be included for both options. I'm asking $300.00 plus shipping. If there are any questions please feel free to PM here and I'll answer ASAP. Thanks for looking!!