block cover

基本解释

Pure copper-base material water block provides excellent heat transfer, and anodized water block cover prevents corrosion.
純銅基料水塊提供優良的熱傳導，陽極氧化和水鎖蓋防止腐蝕。
It includes: the out oscillating flow tube, the inner oscillating flow tube, the thermal insulating block cover and the glass vacuum tube.
包括：外層振蕩流熱琯、內層振蕩流熱琯，保溫堵蓋、玻璃真空琯。
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Hydraulic Disc Piston Press is all-in-one designed for hydraulic brake piston press, bleed block & cover and rotor truing fork for convenient pack and use.
本産品爲攜帶收納與操作之便利性，系將活塞推杆、档塊及碟磐調整器等工具整郃設計成一支多功能之油壓碟煞維脩工具。

The second suggests that a rod-like plug can block the hole by slipping across it sideways and stopping large ions from passing, rather like a drain cover stops leaves from entering the mouth of a pipe.
ECONOMIST: Synthetic biology: Expanded vocabulary The