Enter Promo Code on Checkout: QRWXKDNK
Had something like these before but seem to misplace them easily, anyway this one seems pretty good with decent reviews, and comes with extra accessories suited for car/driving use. The one I had was also able to flip up as are these, and it is actually kinda useful when driving when going through tunnels/parkades/underground, you can simply flip up. The one thing is that because it is polarized , it can be good and bad thing because it cuts off the polarized light coming from LCD screens (such as from phones). It doesn't totally blank it out but makes it harder to see. Oh well, that's why you can flip up also if you need a quick glance.
While it does look quite dorky, it also has a slightly larger finger clip, which I actually prefer as it's easier to use one hand to clip it on and off.