Jon,

I'm using 2 each 32 oz bottles in this box. You can get a 64 oz but, it doesn't fit the box without cutting the tray. My planes are no larger than 40 size so it's enough for me. I believe it also helps keep the fuel uncontaminated by keeping 2 separate containers. In other words, I will only contaminate 32 oz at a time. The best price I've found is at Campmor.com. [link=http://www.campmor.com/webapp/wcs/stores/servlet/ProductDisplay?memberId=12500226&productId=13797]32 oz bottle[/link]