My Favorite mounts for the Pulsar Thermion XP50 are the Nightforce X-Treme duty Ultra Light rings in either 1.5 A203 or 1.375 A110 Height. If you have a full length rail the minimum ring height recommended is the NF A110 rings in 1.375 height. You could use a lower ring height if you have an ALG Defense hand guard without a continuous top rail if you want a better cheek weld. Due to the nature of the Pulsar Thermion XP50 you do not need a cantilevered mount to use this optic as the eye relieve is shorter than a day optic. The plus side is it allows you to use a TC Accessories shell deflector to keep your brass at your feet instead of bouncing off your friends head.