。
Could you show me another one?
Literal
Different-one [object-を] show give-could-not [question-か]?
見せてくれませんか uses the negative potential of くれる instead of もらう — both create polite requests, but くれませんか frames it as 'won't you (give me the favor of showing)?' while もらえませんか frames it as 'could I (receive the favor)?' The practical politeness level is nearly identical.