The plastic part of the lower guide on my Standdesk.com broke, and was subsequently crushed as the desk lowered (see attached photo), and they no longer have any replacement parts.

I designed this simplified replacement part, which isn't quite as good as the original part, but works perfectly fine nonetheless. This part snaps on to the bottom of the inner part of the leg, just like the old part did.

Sorry, I forgot to take a picture of the printed part. :(

My desk was purchased in 2016. I'm unsure what years they made it, but you can see the desk that this goes to in one of their old YouTube videos.