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Selfie Showdown: Vote on Zac Efron's hot ride and Sarah Michelle Gellar's flight of fancyby Chris Serico

Circa's weekly series Selfie Showdown returns with Instagram photos of Zac Efron and Sarah Michelle Gellar, who snapped away while enjoying the splendors of transportation.

Efron flexed while enjoying a sweet Dubai ride and a sandy backdrop.

Elsewhere, Gellar appeared to find herself flying the friendly skies.

VOTE | Whose Instagram pic deserves to win this week's Selfie Showdown: Zac Efron or Sarah Michelle Gellar?

Quiz: Why aren't you Instagram famous yet?
You really should be a bigger deal on Instagram.