My Genie SD9000 screw drive garage door opener was installed in 1991 so it's almost 30 years old. I noticed that my garage door was starting to operate past the maximum opening limit and it turned out that the wire spring on the open limit switch was bent and the plastic lever was also broken so the limit switch had to be replaced. I did a little repair work on a faulty limit switch so the garage door could serve as a temporary solution while I waited to buy a new switch. I still have the original owner's manual for my SD9000 which states the limit switch part number is 24454R. However, there is very little information on the 24454R, only a few vendors have a limit switch with this part number. Although some have an interchangeable part number, none of them contain an accurate description or statement explaining that 20113R.S is the new part number 24454R. Worse, I checked Genie official website, it says 20113R.S does not fit SD9000 or other SD series. I then called Genie tech support and tech support said the SD is very old so they have no information on the 24454R and Genie doesn't sell it or have a new part number. Luckily I saw in the Q&A section for this seller that an SD9000 owner said the 20113R.S was good for opening his garage door so I bought two. The seller is very good, delivery is quite fast from Florida to California, ordered Monday and received Friday. Yes, 20113R.S replaces 24454R and fits SD Series garage door openers. Installation is very easy as everyone said. I lubricated the screw rail and my garage door opener now works great.