tnHeb “the gate of Sur” (followed by many English versions) but no such gate is mentioned elsewhere in the OT. The parallel account in 2 Chr 23:5 has “Foundation Gate.” סוּר (sur), “Sur,” may be a corruption of יְסוֹד (yésod) “foundation,” involving in part dalet-resh confusion.
tn The meaning of מַסָּח (massakh) is not certain. The translation above, rather than understanding it as a genitive modifying “house,” takes it as an adverb describing how the groups will guard the palace. See HALOT605s.v.מַסָּח for the proposed meaning “alternating” (i.e., “in turns”).