Zac Efron in His Underwear on the Set of Dirty Grandpa

Zac Efron in His Underwear on the Set of Dirty Grandpa

Zac Efron Runs Around Almost Naked on 'Dirty Grandpa' Set!: Photo

Zac Efron covers his modesty with a toy to film Dirty Grandpa

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Zac Efron in His Underwear on the Set of Dirty Grandpa

Fancy owning Zac Efron's used jockstrap from Dirty Grandpa

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Zac Efron flashes toned torso as he films Dirty Grandpa

Zac Efron flashes toned torso as he films Dirty Grandpa

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