Abstract: An optical accessory mounting device and a method of mounting an optical accessory mounting device are provided. The optical accessory mounting device comprises a first engagement member and a second engagement member, the first engagement member being movably disposed against the second engagement member; one or more urging members capable of urging the first engagement member and the second engagement member apart from each other; a stopper member disposed between the first engagement member and the second engagement member; a counter-urging member capable of urging the first engagement member and the second engagement member towards each other; and wherein the counter-urging member is disposed between the stopper member and one of the first engagement member and the second engagement member to urge the first engagement member and the second engagement member towards each other translationally.