Backrest can be laid to be flat as sofabed function, it makes sofa easy to be sofa bed. 

1. Zero wall function,that means less than 2 inches away from the wall when you open the sofa bed. 

2. Heavy duty 3-stops design,lock and stop perfectly and clearly.3-stops for sitting,TV and sofa bed.

3. Important function "Storage", this is very important to put the sheet and pillow into storage.

4. KK034 adds rivets bushes and double locks  for cycles,smooth,lock stability and commerical purpose.