Works great for blow off hose into growler or bucket. I use them for all primary fermentations with a 1/2” hose.

Excelente justo lo que necesitaba .

Prompt delivery product was just what I wanted.

These need a plastic zip tie on the neck. Tighten with pliers. Will wiggle off so you can use later.

Does not seal well for using CO2 to transfer from carboy to keg.

Saw quite a few reviews on other sites about fitment issues. The ones I received from here for extremely snuggly. Almost enough to lift an empty carboy from the cap alone. Very satisfied with fitment.

Works great and haven't had a problem with them yet.

Seemed to work ok but found air does leak around the seal. I wrapped package tape around the bottom of the cap and affixed it to the bottle.

Used with thermowell and blow off tube. Excellent

I have been looking for a better blow off solution for my Better Bottle fermenters and this does the job. Fits perfectly and doesn't come off like the stoppers do when they are wet with sanitizer and being pulled with a blow off hose.

These are great to have a small blow off on then easily switch to airlock when fermentation dies down. It is nice not having to swap out to a bung when changing over to the airlock. Would love to see something along this design with bigger tubing to be used for the blow off though.

i love how easy these are to use and have two ports on them. easy to switch between airlock blow off tube or thermowell without having to remove a whole rubber stopper. as mentioned in other reviews they seem to fit loose but when you press on one side of a plastic carboy you can still see the pressure in the airlock change too so it's still doing it's job and seals just fine. a must need accessory to their plastic PET carboys!

Fit my carboy. White plastic covers fit snug. Would buy again

With a zip tie I haven't had any of these pop off during fermentation and while moving carboys

Really great to use with a thermowell for keeping track of fermentation temperature and a blow off tube

I have four of these three of which I got in a single order. Two of my four are molded such that 1/2" tubing does not fit snugly. One of them I have to tape them up with electrical tape and hope for the best when using it for a blow off tube one I just don't use at all because the tubing just won't stay on there. The other two are prefect. The design is good but the quality assurance is not.

I use this to connect the blow-off tube to those standard plastic blue 5 gallon jugs. It fits perfectly. I use the larger hole for the blow-off then I thread my digital thermometer cable through the smaller hole. Easy to clean and sanitize as well.

Slap it on a carboy with a blowoff tube. Doesn't get much better than this!

On my better bottles this works very well as a blowoff tube...Once fermentation slows down though I do not think it will keep a seal to use a airlock...but I mainly bought it for a blowoff so it works for my needs

I've used this for a blow off tube for primary and it fits fairly well on top of the carboy but needed to use a zip tie to hold it in place to prevent it from popping off.

I use this in conjunction with an airlock or blow off tube and SS thermowell to monitor temps during fermentation when doing smaller batches in carboys. I've got like four of them now and they all work great. I was worried about fit varying from one to the other but they're all spot on and seal to mouth of the carboy tightly They're easy to clean and sanitize and get the job done without muss and fuss.

And I use them for my Sanke fermenters too!

These cover the entire top of the carboy keeping the glass clean and eliminating the crevasse between the glass and a bung. I had to cut the enter nipple down a little so it was big enough for the airlock to fit in but that was easy.

I much prefer these to stoppers. Racking is easier blowoff is easier second aperture for thermowell should you so desire plus a stylish safety orange color. What's not to like? (Little caps can get lost - keep them in a ziploc in a designated place when not in use to avoid this.)

Using glass carboys with sanitizer on them sometimes the bungs don't stick. These pop on like a lid and stay put. I also like to use the racking cane with air filter and not use the auto siphon. it gives me a little more control of what I pick up when racking.

Seems a little slippery going onto the carboy but I haven't had it come off even in my most violent wheat beers.

I use this with a blow off tube and thermo well for the probe from the digital Johnson Control. Great product!

I love these hoods. I use them with a blow off and airlocks. Great for creating a sterile siphon when using your racking cane as well.

Their casting quality is poor...but I still use mine all the time. It is great for blowoff tubes; 1/2 inch tubing over the larger opening does the job.

I use this cap for when I know my primary will be very vigorous and i'm using a carboy. When I am beginning a batch the cap fits perfectly on my flask for the yeast starter. I use an airlock on middle port and leave the other capped. Must have!!

Much better than a bung! I do use mine for transfer. I use a hose clamp to seal around the racking cane.