This anti-reflective device is made of aluminum and threads into the objective end of the SRS sight for a secure fit. killFlash and flip caps specifically designed to fit together and rotate easily to a preferred position. The caps flip open and "lock" into position, out of the way. The set will add 1.22 oz. and adds 0.32 in. to the height, 0.626 in. to the length, and 0.066 in. to the width.