Hi @user54953. I would first try to figure out the make and model of your chime and make sure it's compatible with your Doorbell. If it's the Pro, use this [compatibility chart](https://support.ring.com/hc/en-us/articles/209028546-Ring-Video-Doorbell-Pro-Chime-Kit-Compatibility-List), and if it's the Pro 2, use this [chart](https://support.ring.com/hc/en-us/articles/360059789591-Ring-Video-Doorbell-Pro-2-Chime-Kit-Compatibility-List). Once you find out if it is compatible, use this Help Center [page](https://support.ring.com/hc/en-us/articles/115005974286-How-to-Install-Pro-Power-Kit-V2-for-Ring-Video-Doorbell-Pro) on how to install the Pro Power Kit. If you are not sure what terminals would represent front and trans, I recommend reaching out to the manufacturer of your chime for help.