Professional ATC Sea Water Salinity Refractometer w/ 35ppt Calibration Fluid for Aquarium, Hydrometer, 0-100ppt & 1.000-1.070 Salinity Specific Gravity

I am very pleased with this purchase. This kit makes testing my reef tank's water very easy. The hard case is nice for keeping the equipment together and having the calibrating fluid is essential in getting an accurate reading. The refractometer itself is well made and easy to operate. The directions are somewhat vague but if you really have a question about how to calibrate there is always online videos galore showing you exactly how to do it. Very pleased with this purchase and the value.

It did not come with calibration fluid and I purchased this item over others because it included the calibration fluid. When I contacted the seller he said, "this is the new version refractometer, which has been calibrated well, you can use it to test salinity directly,so no calibration fluid included."

this product is very poorly constructed with little to no quality control, eye piece wont adjust because a piece of thread material is stuck between theads and when you look throught the eye piece you can atually see the piece of materal that is causing the issue. you also cant see the scale because of the obstruction. im not taking the time to send this junk back. they can give refund my money or take the bad review but i would warn you not to buy products that show poor quality control!

I love that this comes with a small bottle of salt water calibration fluid. I read so many forums where their refractometer was off from using RD/DI water to calibrate. I really didn't want to spend the extra money for a bottle of calibration fluid, so i bought this unit. its perfect.