The ESCO YAK line of lifting equipment is the highest quality jack available. These jacks are 100% made in Italy and come with an extended 3-year warranty. All YAK jacks are tested for quality and functionality and no jack leaves the facility without being fully tested. All pneumatic parts are made of brass, aluminum or stainless steel. All units have brass air motors, opposed to aluminum or steel, which helps prevent or eliminate corrosion. Other air descending jacks on the market force air into the hydraulic cylinder to push the hydraulic fluid back out to lower the jack, this lets moisture and other contaminants inside your cylinder which causes damage. ESCO YAK Jacks utilize a venturi valve set-up that sucks/pumps fluid back out of the cylinder head to lower the jacks. In turn you never push compressed air into the cylinder, thus extending the lift of the jack by many years.