The first time I tried the reCap on my Mason jar containing my daily nutritional shake, I made a huge mess of my kitchen and my face. Be sure to place the Mason jar firmly on the counter when you are trying to get the cap on the jar. Getting the cap on is not always easy "” the threads don't catch readily, but they do with some work and a few attempts. That's why you want to place the jar on a firm surface "” until you get used to how the reCap goes onto your jar, you may do a lot of spilling.

Be sure the threads and the top lip of the jar are very clean (no protein powder, food particles, etc.) when you are putting the cap on in order to get a good seal. I've done this from the start and haven't had any leakage issues. Regardless, I don't dare just throw this in my bag to go about my business "” the flip cap part seems like it could pop open fairly easily and spill the contents everywhere. I've been placing my jar in a large freezer bag with a zip top so that I can take my shake to work and not have to worry about ruining my work bag.

When you drink from your jar/reCap, you have to keep your index finger on the flip cap to hold it open. Otherwise, it will flip down and hit you in the nose. You can't trust it to stay in the open position without your finger there. Also, if there is residue of your drink (a thick smoothie, in my case), it can collect in the flip cap part and drip out onto your face. That happened to me today at work. Luckily, no one saw.

These are definitely overpriced at $28 for four caps. Maybe the price will come down as they gain in popularity. Now that I'm used to the little problems with the reCap mentioned above, I can live with them, for the coolness factor and for the advantages of drinking out of a clean glass Mason jar (I use the Ball Jar Wide Mouth Pint and Half Jars "” PERFECT size for drinks). I also plan to use these caps to store dry goods like rice in Mason jars, though I haven't tried that yet.

For a long time I've used the cruets that you can buy with a well known seasonings company's (heavily salted) dry dressing mix). But over time, the plastic tops of those have worn out (the plastic of the spout covers have broken and thus are no longer attached). I started using mason jars (which really do allow better mixing when you shake), but the separate, 2 part tops are a pain. By the time you get them off, the dressing is starting to separate, also very messy. Found these guys. A bit expensive, but I'm finding that they're definitely worth it. They are solidly built. I have no worries about premature/easy breakage. There's a nice opening which dispenses the dressing well, I can shake it up in the Mason jar which mixes better than the old cruet, the top covering the spout pops off quickly and easily, it's attached so it won't get lost or get the counter dirty, and it closes quickly, too. Just a light wipe and all done, so it's clean. Seals both the jar and the dispensing spout tightly, I've had no leaks at all (I do, however, just as a precaution keep a finger over the pouring spout flap cover when shaking, though!). Cleaning is easy, you just have to remove (that's a little tricky, but not hard) the silicone O ring, wash everything, let it dry then put the O ring back. Very pleased that I got these. I would definitely purchase again if/when needed (but that could be a while, because as I said before, they are very well made). I paid full price for them, this is my honest review without any remuneration.

I wanted to support a USA company in my search to make storing liquids in glass jars easier. These are great for keeping dressings, aloe Vera juice, olive oil, and I assume will be great for holding milk for trips.

I was a bit hesitant to purchase these caps/lids because some were saying they leaked pretty bad but so far I have had no problems.
I use wide-mouthed ½ gallon mason jars for iced tea and the 2-piece lids were annoying and rusty.
I washed one of the caps immediately after it arrived today and replaced one of the 2-piece lids on my jar to check it out, and it worked beautifully. I shook the jar, turned it upside down, and poured a glass of tea and there was no leaking at all.

I did see some say that it only leaked when hot liquids were in it. Shortly after my first test, I made a new batch of iced tea and the liquid was warm (not hot - I pour a little boiling water to brew the tea in the jar for about 5 minutes but then fill the rest with cold-filtered water). I shook to mix the tea and sugar and there was no leaking at all. I can't speak to whether or not it would leak with hot water and probably will never be able to because I don't fill anything glass (even mason jars in spite of their sturdy tempered design) with boiling water due to fear of shattering or cracking. But for warm or cool liquids, these caps are freaking amazing.
On top of all of that, the pour hole is a perfect solution to the potentially messy pouring situation you can get into with wide-mouth jars.

I haven't washed them in the dishwasher yet but if anything bad happens to them I'll update this review.

I purchased these for use with the half gallon mason jars (for iced coffee & iced tea).

I brewed my first batches, put the lids on and left the jars on the counter to cool before putting them in the fridge -- but thought I'd try one of the warm beverages. I was VERY disappointed when the rims leaked when pouring--huge mess. Checked the gaskets, made sure they were on tight... the only way I could pour with these was with a towel wrapped around the edge to contain the leaking liquids. I was upset that I spent nearly $30 on these and just put them in the fridge, figuring I'd try to find some new gaskets. At that point, I very much regretted this purchase.

The next day, I tried again. The jars, (tea & lids) were properly chilled at this point. NO LEAKS! And consistently, these lids have performed perfectly since.

I believe that perhaps the glass jars and the plastic lids expand differently when exposed to heat, making the lids a poor fit when hot. But they are perfectly fitted when the jar & lid are both cold. For me, it's "hit-or-miss" with room temperatures, but it's not problematic because I wanted them for chilled drinks. (I imagine that they will work perfectly for dried goods as well.)

Excellent product. Very happy that I've got them and they work perfectly for my intended use. It would have saved me the angst of going a night thinking that I made a bad purchase if I had known that the temperature of the jar/contents/lids mattered. Thought it was worth passing along.