noun
hex socket head cap bolt
A bolt with a hexagonal recess in the head, tightened with a hex key (Allen wrench). Technical term used in mechanical engineering and manufacturing.
この部品は六角穴付きボルトで固定されています。
This part is secured with hex socket head cap bolts.
六角穴付ボルトを締めるには六角レンチが必要です。
You need a hex wrench to tighten a hex socket head bolt.
Compound of 六角 (hexagonal), 穴 (hole), 付き (attached, with), and ボルト (bolt). The abbreviated form 六角穴付ボルト drops the okurigana き.