NBA's Chris McCullough Shells Out $100k For Iced Tea ... Chain

With a nickname like Brisk, you gotta look the part ... and that's exactly what Chris McCullough did ... droppin' a ton of cash for his new chain -- a Lipton Brisk Iced Tea can!!

TMZ Sports has learned ... the 2015 1st-round pick wanted something that would symbolize his unique nickname, so he hit up Moses the Jeweler in NYC to hook him up with the one-of-a-kind piece.

We're told the piece -- which is made with 14k white gold and heart and arrow cut diamonds -- took about 6 MONTHS to complete due to all the details.

BTW -- Moses is the same dude who made a $150k gold chain of Larry David's face for producer and manager David Weintraub.

So naturally, his stuff ain't gonna come cheap. We're told…