The reflex optical sight means you can fire with both eyes open.

它配有反射瞄准镜，你可以睁开双眼射击。

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Finally, simplicity of aiming was achieved by use of integral reflex type collimating sight and integral laser aiming module.

最后，旨在实现了由简单的积分使用反射式准直激光视力和整体目标模块。

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By some strange reflex that I had previously never used, I picked up the line - my first and last sight of the ball, I might add - and opted to leave it well alone.

BBC: Facing England's tormentor