Hi,
Let's start with the following link. Copy and drop this, and I invite you to check out the customer questions and answers.
You can reach out to me or anyone else in our help department tomorrow/Friday.
https://www.swisco.com/replacement-columbia-door-roller/pd/Patio-Sliding-Screen-Door-Replacement-Rollers/
84-064thank you for choosing Swisco.com.
The white nylon assy that has 3 holes bottom and one larger hole 10 - 32 on top and threaded inside to adjust the assy that holds the rollets