Apt letters missing from "c_ _tom_ _ _"

USERS

Not available

The clue plays with the phrase "customers" by dropping the letters "U" and "S" (which sound like "users"). The blanked-out word "c_ _tom_ _ _" hints at "customers," and removing those two letters leaves you with "ERS"—but the answer is "USERS" because the missing letters themselves spell it out. It’s a clever twist where the "apt letters" (the ones that fit the wordplay) are the solution.