Under Water Yoga What Do You Have In The Truck Of Your Car Right Now?

What do you have in the truck of your car right now? - under water yoga

I have a yoga mat, my spare tire, the battery of my car (weird I know, never see other than on the cover) a bag with extra layers, water bottles, baby carriages and a double-team of emergency failure. All this and still save space on large trunk. What is it?