The word "master" in this description is throwing me off. Should I be using this model at all 3 locations or is there a companion version I need to know about?

Hello Alizabelly, thank you for your inquiry! The Lutron CA-4PS is a 4-way switch from the Claro/Diva series, and the term "master" can be confusing because it's more commonly used in dimmer or smart switch systems like the Maestro series, where a master switch controls the load and companion switches communicate with it. However, the CA-4PS is a standard mechanical switch, not a smart or dimmer switch. Here's how it works in a multi-location setup: ✅ When to Use the CA-4PS: Use one CA-4PS in the middle location of a 4-way switch setup. Use two CA-3PS (3-way switches) at the end locations. No companion switch is needed—this is not a smart system. For more questions or concerns, contact our Support Team at support @lutron.com or 1-844-LUTRON1.