Torx? It's Stihl so it'll probably be a T27 if so. Try something like one of these for a ratchet.

https://www.amazon.com/Wiha-77113-8-Inch-Socket-6-Inch/dp/B002QPX09U/

Or something like this for a torque driver.

https://www.amazon.com/Wiha-74590-152mm-Torx-Power/dp/B00XIPIAEM/