BlueLab PH 4.0 Calibration Solution, 500 milliliters
</br></br>
<div style="text-align:left">
<b>[Product Information]</b><br>
<ul>
<li>PH instruments are calibrated to pH 7.0 first (buffer) then to pH 4.0 (slope)</li>
<li>Store in a cool place out of direct sun and heat</li>
<li>They should be stored with the lids securely tightened</li>
</ul>
</div>
</br></br></br></br></br></br></br></br></br></br>

</br></br></br></br></br></br></br></br></br></br>
<img src='http://ecx.images-amazon.com/images/I/31O38l6JLyL.jpg'></br>