I added them myself, 10", these are what I installed: Durable Hydraulic Gas Strut Lift Support Kitchen Door Cabinet Hinge Spring Brass | eBay
Others said they used the 50NM but they where not available, I think I had to go with the 80nm but they work fine. This is basically the amount of force they push out, so mine have more power! The instructions did not work for me, I had to mount them different. I think I had to have the top mounted higher, otherwise they would not close. Mess with one, get it to work then measure for the rest of them, piece of cake after the first one. MAKE SURE YOU DRILL PILOT HOLES! I was actually impressed, the wood is pretty hard, broke a screw or 2 screwing it in. Pretty simple mod but a must have for sure!