Refractometer????

[mr9iron]

I've been looking for a refractometer for a while and being budget conscious I found this (http://cgi.ebay.com/Salinity-Refractometer-ATC-Aquarium-Pond-Hydrometer-50_W0QQitemZ120219030440QQihZ002QQcategoryZ111537QQssPageNameZWDVWQQrdZ1QQcmdZViewItem) one. Is this adequate for reefing? I like the fact that it has a 5 year warranty.

[snulma1]

Specifications

Measuring range: 0-100 PPT of NaCl ( ‰ ) and 1.000 - 1.070 SG (Specific Gravity)
Resolution: 1 PPT / 0.001 Specific Gravity
Compensation temperature range: 10°C-30°C
Calibration: zero calibration with water at 20°C
Built-in automatic temperature compensation system (ATC)
Calibration: zero calibration with water at 20°C

Looks good to me!