key lock

Thanks for posting. Since your thumb lever is offset, you will need to replace your outside pull with our 82-044 Outside Pull. You can then adapt the 82-315 Key Lock & Housing to this new pull. See the video below for details on installing the key lock.  

Ah, let me clarify. By offset I mean the positioning of the thumb lever between the mounting holes: if it's not flush-center, then it is offset. The reason this matters is because your outside pull only has room to install a key lock at its dead center; thus, it would not properly meet with the thumb lever tail of your inside handle. Both pieces must be perfectly aligned with where they interact with the mortise lock inside your patio door. Therefore, the simplest solution is to replace your outside pull with something like our 82-044 and adapt to it the 82-315 key lock, which you can install as offset. Alternatively, you also could replace your entire handle set with something like our 82-086. This comes built with an offset keyed lock.