If you are replacing an existing sleeper sofa mechanism or purchasing a fabric deck repair kit for your sleeper sofa mechanism, obtaining the manufacturer and model number of your current mechanism is critical to ensuring you receive the correct product. This is the only reliable way to match parts, since many models of mechanism can be very similar, but not the same, in appearance and dimensions. The model number sticker will contain a variety of information and may appear in several different formats. The two pieces of information you’re looking for here are the manufacturer’s name and the size or model number. Leggett & Platt and Hickory Springs are the most common manufacturers. This will be different than the company that made your sofa (Ashley, Broyhill, Simmons, La‐Z‐Boy, etc.)
If you cannot locate a sticker or are retrofitting a sofa, the following information will assist in narrowing down your needed mechanism manufacturer and model number. 
The first measurement will be the mounting bracket to mounting bracket points to confirm a width match. This is the point on each side of the sofa to which the metal sleeper unit is attached. 
Next, you will want to measure the depth inside the sofa from front to back. 
Then its height capacity. When folded into the couch, measure the height from the floor to the top of the unit. 
Lastly, can you confirm if your unit has a rounded or squared-type frame? 
This information will get us on track to doing an educated guess on a replacement unit for you with as little room for error as possible. 
Please note that when replacing without the make or model number, we rely on the information you provide to make a best-educated guess. Sometimes, modifications, such as a different mounting position, will have to be made to house the new sleeper mechanism.
We know this is a lot of information. Please let us know if you have any questions at this point, we are certainly happy to assist.
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