NOS systems are calibrated for optimum performance with a bottle pressure of 900- 950 psi. The pressure will change with temperature. Heater kits are thermostatically controlled (except P/N 14169NOS, which is pressure controlled) to keep the bottle at correct pressure. Kits available for the most popular-sized bottles, with both 12-volt and 110-volt heaters offered. Available for Most Popular-Sized Bottles.This item is in the category "Vehicle Parts & Accessories\Car Performance Parts\Other". The seller is "vpwaust" and is located in this country: AU. This item can be shipped worldwide.