A review of the Sightmark Ultra Shot M Spec as done by Hoplopfheil... "Sightmark has a reputation as a joke company that makes airsoft grade optics, including the Ultra Shot red dot. But they also make the "M-Spec" variant of the Ultra Shot which has a more serious design and featureset, and a much higher price tag.
New release from Sightmark, the Sightmark Ultra Shot M-Spec FMS Carbon Fiber Reflex Sight... "A special offering for Sightmark’s 10th year anniversary, the all-new Sightmark Ultra Shot M-Spec FMS Carbon Fiber takes advantage of the same advanced optical design of other trusted M-Spec models, but features a real carbon fiber protective hood, helping it weigh in 30% lighter than popular reflex sights from other manufacturers.