SP10841OM - Hayward WG Auto-Skim In-Ground Pool Skimmer, Square Lid, 1.5"Hayward SP10841OM Auto Skim Through Wall Outside Mount Skimmer. The Hayward SP10841OM skimmer is designed for use with in ground vinyl liner and fiberglass pools. The SP10841 is molded of rugged, non corrosive ABS plastic and features no joints below water level making it very durable. This skimmer has a large capacity basket and a weir.