Kokido Kafra Dual Solar Dome Swimming Pool Water Heaters & Bypass Kit The base is made of PE, the transparent cover is made of PVC Max. Flow: 925gal/hr / 3.5m/h Capacity 5.5L / 1.45 gal Max pressure: 0.6 bar / 8.7 psi 2 x side hose connectors with O-ring