Doesn't come with the diffuser, but good product
930845
Love the Sentry Calming collars and have high hopes for this, but I misunderstood that the diffuser doesn't come with this, so I need to find a diffuser to try this.
906119
This is perfect for my needs and by far the best diffuser I've owned!
1481307
This is a very cool product at a terrific price, very happy with the purchase.

One recommendation, get the diffuser for the extra $4.95, totally worth it...
679535
I believe this diffuser does the job, as I have used them in the past on a gas stove. I recently bought this model to use on my new electric cooktop. However, I should have read the reviews first, at least the review that says it is 8.5" in diameter. Instead, I read Amazon's product information that says it measures 6" in diameter. That is, it measures 2"x 3" x 6" with 6" logically being the diameter. (I won't comment on what the 2" or the 3" measured. )Now 6" diffusers are hard to find, but my cooktop has several 6" elements, so this looked like a perfect fit. But when it arrived, the first thing I saw was the printed tag saying it was 8.5" diameter. The problem was I had also ordered an 8" diameter diffuser. So I ended up with 2 diffusers, both 8" and no 6" diffuser. Those Amazon specs can really be misleading sometimes. It is better to  incorporate the diameter size in the product's main description. As it now stands you have to hunt hard for this basic measurement. So I have returned this diffuser due to an error in the product description.
44251
So far I am enjoying this diffuser. I just wish it came with one or two samples of oils. I really can't put it to good use until I research oils!
1388798
It is smaller than expected but fairly bright, the light adjustments are a little difficult to navigate.. may need more practice.
The diffuser is excellent!... I have fount that sometimes LED lights are actually too bright when working close up, The diffuser helps with that quite a bit.
1301061
I wanted to write a review for this product because I think the heating element in the diffuser is SO much safer than the one in the Feliway Comfort Zone diffuser. This one is not feeling overly warm, the product is not smoking (unlike the Feliway diffuser) and the product is being used slowly (my feliway diffuser was empty in just about 18 days, instead of the month you were supposed to get from it). Also, part of the plastic on my feliway diffuser had browned in a way that suggested overheating or burning. I was actually nervous to use it.  The sergeants product is fabulous.

The effect of the product is hard for me to judge, I bought this to calm an 18 year old cat who has started to pace and meow very loudly sometimes. She's calmed down a lot, but I'm not really sure if that's because of the diffuser.
HOWEVER, the superior heating element should be something to consider if you are trying to choose between the two products.
2627761
I have never had one of these but I've been looking for one as I've been into essential oils for a while now. I saw this one and decided to order and give it a try.  It came quickly by mail and well packed to prevent damage.  It's about 6 inches in height and white with a nice, modern design.  It looks good with pretty much any decor and is made of a lightweight plastic.  The unit has rubber feet on the bottom to prevent it from moving and keep it more stable.  The design of the diffuser is excellent as it is wider on bottom to prevent it from falling over since it is light and really easy to use and clean after use. Cleaning is recommended every 2-3 days to prevent bacteria and mold from accumulating and entering your air.  Also, the diffuser should be emptied after each use but keep the air outlet on the opposite side from where you would empty the unit and do not touch the ultrasonic unit inside.
  I used this today with about 70mL of water and 2 drops of lavender essential oil.  I will also note that you want to make sure you have no additives or chemicals in your oil to prevent having said chemicals in the air as it diffuses. Next time, I may use one drop of lavender.  I like the smell, but I like it to be light and this might be too strong, but it was still fine even with 2 drops.  After putting water and oil into the diffuser, I then plugged the cord into the bottom, making sure not to tip the water. Then, I plugged it into the wall and it immediately started working after I pressed mist.
  I pressed the light button first, once and then the mist button.  This unit lights up and has a few different colors. It transitions from green-->red-->purple-->blue--->then light blue as it transitions back to green.  If you hold the light button down on a specific color then you can set it to said color of your preference. Otherwise, it changes color over time the entire time it is on(you can also choose no light).  Also, you can press the mist button to start at 30 minutes and then keep pressing to get that or 60,120, or 180minutes and if you hit the mist button again, you can turn it off.  If you choose a time, it will just auto shutoff so you don't have to worry about it.
  This is really easy to use and does come with an instruction booklet.  My only issue with the booklet is that the grammar needs some serious correction but other than that it is fine.  I received this at a discount to test and give my honest opinion.  I am glad I purchased this as my first diffuser and it works well.  I am happy that it is easy to clean and isn't hard to use. You can pretty much put this anywhere as it is a neutral color and looks great with the multiple colors. I'm happy I have this one. =)
3914883
Comes with the light diffuser cover so you don't damage the eyes of those you photograph.  for other types of photography it is great by itself.
1869982
I love this diffuser! It is so beautiful and works really well! The light feature with different colors makes this so much more beautiful!
4692828
The diffuser itself works very well on my Nikon SB-400 flash unit. However, it is hard to carry as it does not fit into the skin tight case that Nikon supplies with the SB-400. My zoom lens camera bag also had difficulty swallowing the rigid plastic diffuser and the net result is that the diffuser has to be carried seperately as a rigid plastic form that will not collapse.

The diffuser itself works very well, spreading the light from the flash and uniformly lighting my subject. It is very inexpensive and Amazon's service in ordering and delivering was very prompt. I was able to make my trip on time. I would recommend this diffuser without reservations if you have a large enough camera bag that will swallow all the gadgets one must carry  in this business. If on the other hand, you are trying to reduce your carrying footprint, buying some sort of a soft collapsible diffuser may be more convenient.
1253901
The umbrella-type mechanism is a snap to open and close for storage. Has only the external diffuser, but that seems to do OK.
3161820
I like this diffuser except when I have to take it apart, I use a jar opener to get the top off, and still have a hard time. Otherwise it works good, and shuts itself off, which is a nice feature.
2907736
<div id="video-block-R2GH0X88VA22WW" class="a-section a-spacing-small a-spacing-top-mini video-block"></div><input type="hidden" name="" value="https://images-na.ssl-images-amazon.com/images/I/B1o9nSMgjaS.mp4" class="video-url"><input type="hidden" name="" value="https://images-na.ssl-images-amazon.com/images/I/9192EjUFMKS.png" class="video-slate-img-url">&nbsp;Amazing Diffuser!
This diffuser is awesome! It has a soft LED light that adds a touch of ambiance and relaxing atmosphere. The light rotates from 7 colors, all of them very soothing (red, yellow, green, blue, purple, pink, white). There is an option to stop the rotation at any color or turn off the light.  The diffuser is also very easy to use, just open up the lid and use the measuring cup to fill it with water, then add 2 drops of the essential oil and turn it on.  The aroma fragrance filled my room for about 8 hours and it automatically shut off when it ran out of water. That was pretty impressive because most of the diffuser I tried needed many more drops of essential oil, and they didn't last this long either! This diffuser worked very well for me. Love it! High Quality!!! Definitely recommend it!
356049
So I have two diffusers, this one and the innogear. The innogear is smaller and has more lighting options. This one is about the size of a wine decanter. Both blow off good amounts of mist. This one is more practical for bigger spaces. Only downside is this product does not have a timer like the innogear. It'd also be nice if they included sample oils in the packaging.
3230412
Like the fragrance and longevity of this diffuser. Only setback is that you need a few of them to actually smell the scent throughout my home and it isn't a castle.
67337
Still use the diffuser!  Works as expected.  Good quality.