密封管

The mainly rubber productions: various rubber special type productions, high pressure tube, rubber airproof strip and tube, resinic tube and so on.

各种橡胶异型件、高压油、橡胶密封条、、树脂等。

The phototransistor was installed through holes in the top of the case, and enclosed in a brass tube that was painted black inside and out.

该光敏三极是通过安装洞上方下，密封一个黄，是手绘黑色内。