If you search for 'digital cameras,' for example, you get the option to narrow your search by number of megapixels, optical zoom, or brand.
比如你在搜索数码相机时，你可以根据像素、光学变焦和品牌等对产品进行筛选。
2
The weapon operator search and locate the target using a periscope optical sight (7km range) in day light, or a thermal imager at night or in bad weather conditions.