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、、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的情况下，密一个黄铜，这是手绘的黑色内。