I saw CtrlAltPrint's Temperature Sensor Server Rack Mount and thought “that looks really handy, but is rather long and uses more filament than needed at the mount point”. I then promptly remixed it into a version that works for me.

CtrlAltPrint describes his model as…

Temperature Sensor Mount for a Server Rack, uses PLA no supports needed. It uses server rack mounting hardwear. Easy to install