The Syncra Silent is new range of energy efficient pumps that is absolutely silent. Don't be fooled - these pumps are powerful and versatile. Ideal for fresh and salt water aquariums, protein skimmers, indoor fountains, water-cooling and all submersible and in-line applications which require high performance and total silence. Thanks to Sicce’s 35 years of experience, Syncra Silent are equipped with a synchronous motor and an advanced rotor which makes the pumps 100% silent. Features all models available with 6' bi-polar or 20' grounded cord flow rates from 185gph to 1321gph ceramic shaft and bearings durable rotor and shaft standard thread intake & discharge barb fittings included resistance to harsh conditions Submersible or inline use adjustable flow rate 7 models available: Syncra .5 Pump: 185gph, 4' max head, 1.73psi Syncra 1.0 Pump: 251gph, 5' max head, 2.17psi Syncra 1.5 Pump: 357gph, 6' max head, 2.60psi Syncra 2.0 Pump: 568gph, 7.9' max head, 2.82psi Syncra 3.0 Pump: 714gph, 9.9' max head, 4.30psi Syncra 3.5 Pump: 660gph, 12.5' max head, 5.43psi Syncra 4.0 Pump: 952gph, 12.6' max head, 5.43psi Syncra 5.0 Pump: 1321gph, 12.6' max head, 5.47psi