From Halopedia, the Halo wiki
Georgi Baklanov made use of SAD-8s before he was killed by the Spartan-II, Kelly-087, on December 12, 2553. When Civilians on Gao approached UNSC forces at the New Leaf Field Complex a few days later, one of them also carried a Defender.
The SAD-8 is manufactured by Sevine Arms, a corporation on Gao. SAD-8s are freely sold to civilians on Gao and elsewhere, notably Venezia. Defenders are short-nosed weapons designed for easy concealment and close-quarters self defense. Their recoil is so heavy that even experienced shooters have trouble hitting a target at ten meters. The SAD-8 has a hammer that can be thumbed and is capable of firing hollow-point ammunition.
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