PHOTOS: Texans' J.J. Watt surprises Houston police, fire departments with pizza

Houston Texans defensive end J.J. Watt is one of the NFL's most intimidating players, but as he showed Tuesday, he's a pretty nice guy off the field. 

Watt treated the Houston police and fire departments to a pizza lunch Tuesday and sent along a handwritten note to thank them for their service. 

The note reads:

HFD & HPD,

I just wanted to send y'all a small token of my appreciation for everything you do. My dad & uncle were both firefighters, so I spent a lot of time around the firehouse when I was younger and gained a great deal of respect for both firefighters and the police force along the way. Y'all show up day in & day out, never knowing what the day might hold and never getting enough thanks for what you do, yet you still continue to put others before yourselves and save lives because of it. As athletes, we often get the headlines and big crowds, but just like the men & women in our military, y'all are the ones who truly deserve the credit, appreciation & admiration. I know it's not much, but please enjoy lunch on me today. Thank you for all that you do!