“Coolrunnings” always provides cool water because it employs a twister-system cooling-pin located below the bottle cap. Convection current is faster and because of the twister-like groove it resists more strongly against water than slotted grooves. Water gets cool when shaken because the cooling-pin located in the center accelerates convection. The cap is made of rubber and prevents water from leaking out of the bottle. As the condenser is grooved like a twister, water is affected by the cooling-pin turning more smoothly.