The items under consideration are identified as Bolt Sleeve (Small), Part # 557420 and Bolt Sleeve (Large), Part # 557430. Each bolt sleeve is made of aluminum that is cold forged, heat treated, and machined. The small bolt sleeve has a shank 20 mm in dimeter, a head with 10 mm of internal threading, and 13 mm of external threading just below the head. The large bolt sleeve has a shank 22 mm in dimeter, a head with 16 mm of internal threading, and 16 mm of external threading just below the head. The bolt sleeve is threaded into an aluminum profile of the battery tray of an electric passenger vehicle. The completed battery tray is then attached to the vehicle by a separate bolt that is driven through the center hole of each sleeve. The bolt sleeve functions to both support the column load of the bolt to prevent the aluminum cross-section of the housing from collapsing, and via the internal threads on the head, to fasten the housing cover to the battery housing.
[1] Please importantly note that only the relevant portion of the related is displayed above. You may refer to the said customs ruling for the entire ruling explanation.
[1]. https://rulings.cbp.gov/ruling/N322122