I rarely post pictures when reviewing something but this cup is so fabulous and the straw lid is unlike anything I've ever owned. It truly is spill-proof, which I tried to show with the photo of the top view. There is a strong plastic (I think its plastic at least) straw to go through the sealed hole, and unless liquid pours out of the straw itself, there's no way for anything to spill! The other lid is not pictured here in my review but is still included and is a normal tumbler lid with a hole to drink from. 

The only thing I might like better is if the cup itself had some texture to it, but really that's not even necessary.  

My ice water still solid after several hours in the cup! Love this thing and will use it A TON.