Bovedafor Cigars | One-Step Calibration Kit | Preloaded with 75% RH Humidity Control Pack | Precise Salt Test for Digital and Analog Hygrometers and Humidity Sensors | 1-count

I use humidity sensors in terrariums. With high humidity sensors will raise the humidity as much as 10% in only a few months. For me accuracy is very important. The Boveda calibration kit worked very well for me bringing the calibration within 1% of the 75% target. I especially like the size as I can calibrate more than one sensor at a time. Depending on the size of your sensors they will fit 2 or more. This best part is the accuracy and ease of use.

The idea is elegant! The magic potion inside the sealable envelope will maintain a stable humidity inside the envelope that your hygrometer must match.Leave it in there for a couple of hours (8, actually) and see what your hygrometer reads through the transparent bag. Then, take it out and turn it up or down, depending on how many clicks or turns it takes to match. Stick it back inside the back to make sure you got it right.I believe that—as long as the bag remains well sealed—the magic goop inside remains potent to maintain the set humidity. (But I used to believe in the tooth fairy as a kid too.)

It's very easy to use. Just place your hygrometer in the bag, seal it. 24 hours later, your hygrometer is calibrated. Put it back to work in your humidor. Don't toss the bag away! It's good for 3 months!! Inexpensive fix!!

Excellent, sound principle. If you have small enough devices (like the Sensor Push) they will fit in simultaneously. There's juuuust enough room to squeeze a Kestrel 4200 in there (to tune the 2nd cycle of calibration). There are more thorough 2-stage cal units, but the price and convenience of this is great. I would've added a Star if it had been an inch taller.

It's a simple product. A bag with a pouch inside. You put hygrometer in, zip it up, wait for it to read 75%. Can be used for up to 3 months after first opening.So I bought an AcuRite hygrometer and wanted to calibrate it just to see how accurate it was (I'm just using the hygrometer for my home this winter). I don't know if I was lucky, or if the AcuRite hygrometer or this calibration kit were super accurate, but as you can see in the picture, mine read exactly 75% humidity. Nice.CALIBRATION NOTE: Calibration may take some time! I think any negative reviews for their hygrometer or this kit come from people who may not know how slowly moisture content changes, especially with calibration. The calibration kit says to keep it in the calibration bag for a minimum of 24 hours. I highly recommend keeping it inside for longer.Straight out the box, I hung my unit for a day and it read somewhere between 60 and 65% humidity in the house. I put it inside this calibration bag and it took 3 days to get to 71%. I almost took it out and calibrated it up 4 percentage points (to 75%), but I kept it inside. Next day it read 72.8% and since it was increasing, I thought to wait and see how high it would get so I left it. I ended up forgetting about it and four days later it was at 74.9%. That’s when I took pictures with it still in the bag. Upon moving the bag for the pictures, the reading fluctuated to 75, 75.1, then back to 75. But I mean, you can’t get much more accurate than that.THE POINT IS THAT IT TOOK LIKE A WEEK TO CALIBRATE EXACLTY TO 75%, so that’s why I recommend leaving your hygrometer to calibrate for definitely longer than a day, and wait before writing a bad review for a “bad” hygrometer or "bad" calibration kit. Moisture is a fickle thing! Unlike temperature.By the way, this is ONE bag. Picture shows "2" bags only to show the front and back.

As described and worth purchasing

I’ve been using this product for years. The absolute best way to calibrate your hygrometers. Has never let me down.

I've used this to calibrate 4 hygrometers so far: 3x SensorPush sensors and 1x AcuRite 01080 Pro.It's incredibly easy to do, just zip the hygrometer into the bag and wait. Once the humidity readings settle, they should read exactly 75.5%.There are a few things to be aware of:1) This is advertised as both a 75% and 75.5% calibration kit. In reality it is 75.5% - but that half % isn't overly meaningful for most hygrometers - especially if they don't report decimal points anyway. Just keep in mind that if yours does report decimal places, you should target 75.5%.2) Be patient! This is advertised as taking between 24-36 hours for the humidity to settle, and I read several reviews where people thought it was done in as little as 6-8 hours. With the ones I've calibrated, they got within 5% of the final RH in the first 6 hours - and were within 2% of the final RH within 24 hours. In all 4 cases, they didn't truly settle until close to the 36 hour mark and I would have been miscalibrating the hygrometers if I pulled them out early.Just remember, if you're going to go through the trouble of calibrating your hygrometer, be patient and wait a full 36 hours. Ending the calibration early won't help if the calibration ends up being incorrect. (NOTE: I wouldn't have even noticed it wasn't done if I weren't looking at the SensorPush graphs on the first calibration - it seemed like it had settled when just looking at the current numbers.)Another thing that wasn't clear to me is that these packs are re-usable for up to 3 months. If you have 3 hygrometers to calibrate, you don't need 3 packs - just calibrate them back to back (which for me, made it even harder to be patient when I realized the humidity level was still creeping up slowly after 24 hours).If you do care enough about the accuracy of your hygrometer to go through the trouble of calibrating them - then I highly recommend using these little packs from Boveda. The overall process couldn't be simpler.

Works as advertised to calibrate an hygrometer.

Adapté pour calibrer un hygromètre.

Very useful tool which you need to calibrate it properly. Put your hygrometer in the bag and forget about for a day or two. Check it back and see if it matches the humidity.

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