Check the listing for details. Rola-Chem M-3000 Swimming Pool, Spa, Pond Sentry Automatic Water Leveler. Condition: New. Listed at 89.99 USD. Rola-Chem M-3000 Swimming Pool, Spa or Pond Sentry Automatic Water Leveler Item Number: 106100 THE POOL SENTRY™ is used to maintain the water level of a pool or spa automatically and unattended. When the Pool Sentry is removed from the box, it is easily assembled by threading the fill tube into the float valve. Snap the fill tube and float valve into the base and fill the base with small rocks or pea gravel. Next, snap the top cover onto the base and attach the garden hose (not included). Finally, adjust the float to the desired position. The supply water stays on at all times when the Pool Sentry™ is in the pool. As the float drops, the water turns on. When the float reaches its set height, the water shuts off. The customer can adjust the float to any desired level, usually a point halfway on the tile line or skimmer. Because the hose is under constant water pressure, it is essential that the customer uses a heavy-duty, reinforced hose. A flyer in each box offers customers an aftermarket hose. It is rated to 200 psi working pressure and 750 psi burst strength. NOTE: The water stays on at all times when the Pool Sentry is in the pool. Because the hose is under constant water pressure, it is essential that you use a heavy-duty, reinforced hose. Instructions for Assembly: Thread the fill tube into the float valve Snap the fill tube and float valve into the base Fill the base with small rocks or pea gravel Snap the top cover onto the base and attach a garden hose (not included) Adjust the float to the desired position 1 Yr. Limited MFG Warranty