Extech RH300-CAL Humidity Calibration Kit<div style="text-align: left;"><strong>[Product Information]</strong><ul><li id="replacementPartsFitmentBullet" class="aok-hidden" data-doesntfitmessage="We're not sure this item fits your " data-fitsmessage="This fits your "><span class="a-list-item"><span id="replacementPartsFitmentBulletInner"><a href="#" class="a-link-normal hsx-rpp-fitment-focus">Enter your model number</a>to make sure this fits.</span></span></li><li><span class="a-list-item"> Optional calibration kit for calibrating extech humidity meters </span></li><li><span class="a-list-item"> 33% and 75% relative humidity bottles </span></li><li><span class="a-list-item"> Bottle designed with small opening for snug fit of the sensor probe </span></li></ul></div><img src="http://ecx.images-amazon.com/images/I/41iruBT2HkL.jpg" noproxy><img src="http://ecx.images-amazon.com/images/I/31CVMWocutL.jpg" noproxy>