Updated:

Original review is below and still stands. Increasing star rating after the store owner graciously refunded the purchase and offered a replacement.
I am not accepting the replacement and will be buying a different brand, however.

James, the owner, believes that gravity filters are becoming the norm in this industry. That may be true for several simple reasons. You'll have to make your own assumptions. So be it. With the set that I tried to use, the coffee first runs through holes that allow greater flow than the lower filter plate can handle. And the rate is much higher than the Vietnamese drip rate. This forced most of the water/coffee to flow out between the filter and filter plate.

So what I received has several possible problems:
Holes are poorly made in the filter or filter plate.

Product doesn't have enough weight to stop this leakage.

There is damage to one part or something is misshapen. (Likely due to the product being shipped in an envelope versus a box.)

Whatever the problem, the set I received needs a screwed filter to work properly. The gravity filter simply allows too much water through. The grinds used should be ideal for this device. None fell through and obviously water made its way through them. They were leveled and tamped and allowed to "bloom". If anything they should have slowed the flow rate.

Customer service is commendable and refreshing but I cannot rate higher than three stars for something I threw away.

"”"”"”"”"”-

These do not have screw down filters. That's a key part of the design. During testing I lost half of the coffee/water and had to soak it up because of this. The water couldn't make its way through the filter layers before being pushed out the side. They would have to be used without the larger piece that goes on the container being drained into. Which means... mason jars based on the size of the 8 ounce item.

Also, the measurements are the maximum amount that the cup can hold. That is without coffee. 8 ounces of water will not work with coffee inside. I was thinking that 8 ounces would be what each use would make.

I should have read reviews. Shame on me. These sets are useless.

Love these things... great if you like to tinker and adjust to make the perfect cup of coffee to your taste.

Keep in mind that these are the "gravity" inserts (not the screw ones). It gives you a little less adjustability than the screw ones in terms of how fast the water goes through... but easier to clean and less parts that can rust compared to the screw-in one.

Tip: You can use more coffee to make it drip through slower. Make sure to "bloom" the coffee by pouring just a little water over and letting it absorb before you fill the whole reservoir up.

I had been pining away for a chance to head down to my favorite Vietnamese place, mostly for another cup of fantastic coffee. I somehow (in my caffeine deprives state) figured out I could get a similar filter from Amazon. One quick search and two days later I had these filters in my hand! One for me, one for a friend who appreciates all things coffee. I was unsure of what size to get for my super sized mug and went with the 11 ouncer, which was 100% the exact right call! I could French press my grounds or perk them, however for an elegant take on after dinner coffee nothing tops a Vietnamese Coffee Filter. A thin layer of sweetened condensed milk in the cup and the coffee starts bitter, like my heart, and ends sweet, like the start of vacation. The filter works great and I'll probably buy more to give as gifts.

What a great idea! I do not know how these little filters have not caught on and replaced the wave of Keurig machines. My wife and first experienced Vietnamese iced coffee at a French bistro in Spain! When back in the U.S. we recently visited a Vietnamese restaurant and my wife was excited to see Vietnamese coffee on the menu. She ordered one and it was brought to the table in one of these little filters. I immediately went to Amazon, found them and ordered 2. It is so easy to make a single cup of coffee and what I like is that you can control the strength. I am not a big coffee drinker but when I do, I love a very strong coffee. By packing the grounds and allowing a long steep, this little filter makes a great cup. You can play around with the amount of coffee (something I was unable to do with a refillable Keurig pod) and the steep time to make just the perfect cup. Much easier to clean than a french press! I am going to give these as gifts to all my coffee drinking friends.

Well, after reading all of the great reviews for these coffee filters I was very excited to start making Vietnamese coffee at home but its not been a good experience so far. The filter seems to be fairly well made, and the process is pretty straight forward. I purchased the Trung Nguyen Vietnamese coffee Premium blend to go along with the filter and have tried several times to make coffee with that as well as some standard grind Folgers from the grocery store. No matter what I try, the coffee takes at least 30 minutes to drip through the filter. The only conclusion I can come to is that the holes in the filter are too small to let the coffee drip through at the proper rate. I have to believe that the filter I received is an anomaly since most of the reviewers seem to be having a good experience with theirs. I guess I will see if the seller stands behind their product, I will update this review after I see how this situation is handled. 2 stars.

Update 7/25/17: OK, I'm impressed. I received an email from the seller, Fitzy Shop within 24 hours of posting my original review, notifying me that they were charging back the purchase price of this item to my account. Obviously good customer service is very important to this seller and I am very happy to recommend to anyone that they should purchase from Fitzy Shop at any time and feel comfortable knowing they will be taken care of. While I am still disappointed that I can't make the Vietnamese coffee that I wanted to (I will figure that one out), I am updating my review from 2 to 3 stars based on the customer support. Thank you Fitzy Shop for being the kind of conscientious seller that makes it pleasant to shop on Amazon.

Update 8/25/17: Once again the seller Fitzy Shop has surprised and amazed me, so much so, I have upgraded my rating to 5 stars. I was unable to post this update right away, but shortly after posting the charged back purchase price, I received notification of a pending delivery from Amazon. A week later I received not only a new 15oz. filter but also an 11oz. filter from Fitzy Shop. The 15oz. filter is a screw down type, so it is slightly different than the original one. I have not tried the 11oz. filter yet , but the 15oz. does seem to work much better than the original one. Obviously you can feel completely comfortable ordering from Fitzy Shop, they definitely stand behind their products, and have a customer service policy second to none. I applaud you Fitzy Shop for your integrity as a seller, and trust me, I am telling everyone who will listen, to purchase from you if they ever get the chance to. Thank you, Thank you, Thank you.