Rob Gronkowski has a lot to smile about during the coronavirus pandemic ... the retired NFL superstar's teeth whitening business has seen a MASSIVE increase in sales ... and now he's paying it forward.
TMZ Sports has learned ... Snow -- which is part-owned by Gronk and UFC legend Chuck Liddell -- has been inundated with orders for the teeth whitening kits since the outbreak.
Josh Elizetxe tells us sales have increased by 240% and the orders are still coming in strong -- most likely due to an influx in video chatting while people work from home.
"We are shipping around the clock from Arizona to our customers’ doorsteps to help them feel more confident for those video calls and social distance selfies," Elizetxe tells us.
But, all the profits ain't going to line pockets -- Snow has decided to donate proceeds to help smaller businesses survive during the pandemic.
Gronk tells us ... "I'm excited that we as a company have decided to donate proceeds from every order on TrySnow.com to small businesses across America affected by COVID-19."
Now, that's somethin' worth smiling for.