Customer Reviews Accessories & Related Products CrystalClear TrueRock Mini Boulder Covers 10"L x 8"W x 5"H MSRP: Was: Now: $74.99 CrystalClear PondAir Diaphragm Compressor Maintenance Kits MSRP: Was: Starting at $12.49 CrystalClear PondAir Air Stones MSRP: Was: Starting at $4.99 CrystalClear PondAir 30' Airline MSRP: Was: Now: $6.24 Item Numbers and UPC Item Number 490316 UPC Code 811262010986 Unit CrystalClear PondAir Check Valves - 2 Pack