[Q] Htc One Unroot, which RUU do I use? topic

Okay so I rooted my htc one and now I need to go back to the stock rom on my htc one because I need to send it away for warranty.
But I'm confused on what RUU to use I bought the phone in Ireland on the O2 network, my phone is also sim unlocked. Will running a RUU lose my sim unlock?
Is it possible to run a RUU on my device. Thanks in advance.
HBoot: 1.54.0000
Radio: 4a.17.3250.14
Os: 2.24.206.7