Nike double pocket flask belt 20ozsweltering days wont prevent your daily run when you have nikes double pocket flask belt attached to your hips the two flasks included with the belt hold up to 20oz of fluid 10oz per flask which will keep you suitably hydrated while out on the road ergonomic lightweight and comfortablethe pocket flask belt has many features for something so simple such as a stabilised design form fitting belt which curves to your body and reduces bounce a zip pocket so