For Duck Dynasty’s Si Robertson the one item he can’t live without is his blue Tupperware cup.

Uncle Si Robertson explains the full story behind his unusual accessory for the first time in his new book, Si-cology: Tales and Wisdom from Duck Dynasty’s Favorite Uncle.

He first acquired the blue Tupperware container when his mother sent it to him in a care package during his time serving in the military in Vietnam.

“Somehow, Momma’s iced tea cup stayed with me all the way through Vietnam, and I’ve carried it in my back pocket ever since,” Si Robertson writes.

Si Robertson explains the full story behind his blue cup for the first time in his new book

“I guess if it can make it through the napalm, mustard gas, and rice wine of Vietnam, I’ll probably take it to my grave.”

Si Robertson says he never lets the cup out of his sight, and he wouldn’t part with it for the world.

“One time, a guy handed me a blank check and wanted to buy my iced tea cup,” Uncle Si claims.

“<<Fill in the amount>>, he said. <<Whatever it takes. I want that Tupperware cup>>.”

Si Robertson continues: “<<It’s not for sale>>, I told him. I told the guy to go buy his own Tupperware cup …”

The Tupperware brand has been thrilled with all of the prominent product placement the blue cup gets on Duck Dynasty show, and sent Si Robertson “a stainless steel saucepan with a lid, a big boiling pot, and a really nice set of steak knives,” plus a dozen blue cups, he claims.

“Apparently Tupperware cups are making a comeback,” Si Robertson writes.

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