They feature a lightweight, durable "disc float" suitable for temperatures up to 180°F (82°C) which closes the atmospheric vent to prevent spilling under all rates of flow. Therefore, they are ideally recommended for low flow installations such as laboratory equipment which use such a small amount of water. They also contain a durable silicone disc which has high heat and water hammer shock resistance and assures tight seating with the lightest of seating contact.
Full Size Orifice - Series 288A has a full-size orifice to assure pipe size capacity. Water passages are streamlined to provide high water flow with minimal pressure loss.