MAGNUM_MEDIA's "REEF METER" NATURAL SEAWATER Salinity Refractometer for Salt Water Aquariums (20-40ppt) & 1.015 to 1.030 S.G. DUAL SCALE Hydrometer MAGNUM MEDIA's "REEF METER" Dual Scale NATURAL SEAWATER Salinity Refractometer - 20-40 Salinity ppt & 1.015-1.030 Salinity SG THE most accurate way to measure Salinity in your tank or envirnment! Comes in a HARD PLASTIC CASE with pipette, calibration screwdriver and users guide Perfect for the PROFESSIONAL Reef Tank Enthusiast or Wildlife Professional Sturdy Design - MADE of Professional Grade Materials - 5 Year Warranty - through Magnum Media ONLY!