Strida Quick Release Seat mount
The Strida Quick Release Seat mount makes it easy to change the seat height in seconds without tools. If you share your strida with someone else, this is a must have accessory. Comes standard on EVO models and SX model Strida bikes.
Here is a link to a post, Strida QR Seat mount Explained.
Here is a link to the Strida instructions for the Strida Quick Release seat mount manual.