BVV 3 Gallon Wide Stainless Steel Vacuum Chamber with Reversible Silicone Gasket, Glycerin-Filled Gauge, 50-Micron Air Filter, Degassing Chamber with User-Friendly Connections - Made in USA

I'm using this for stabilizing wood and it works great. After pulling a vacuum I can close the valve and turn off the pump and the vacuum holds fine. I cycle the pump on/off every couple of hours to make sure the pump doesn't overheat.

For starters, I am using this chamber to encapsulate solar cells in EVA to prevent oxidation. As such, I am much more picky than users for less demanding applications. I ended up buying this mainly because BVV customer service was so clueless, that I didn't have a choice if I wanted to see if it would work for my application. I submitted two questions online: First, what is the dimensions of the chamber? In the pictures it looks like it wider at the top than the bottom. I got a response that simply copied the description (8" tall and 10.5" diameter) no top/bottom inside/outside. I am using a temperature controlled induction hot plate for my setup. Not all SS are non-magnetic and some alloys are suitable for induction heaters. Since the description mentions stainless steel, but not the alloy, I asked BVV if the chamber was induction compatible and I was told that I should not use an open flame?!?!?! For the record, it is not induction compatible so you will have to use an adapter plate.Now that I have had the chamber and had a chance to test it, I wanted to answer some of those questions. First the chamber has vertical walls even though the picture seems to show otherwise (perspective I guess) outside diameter is 10.5" and inside usable diameter is about 10" at the flat bottom. The chamber is thick and heavy and is well made with a nice finish especially at the critical sealing surface at the top.The best part is the fittings. The Vacuum gauge is high quality and glycerin filled after I zeroed it by venting the cap, it read perfectly accurate and smooth with no sticking. Unlike most every budget chamber you see on amazon, this one has actual R-12 style HVAC quick connect fittings and they include a high quality hose. This is the same connector that is on most small vacuum pumps (I was using a Robinair) and it makes a HUGE difference in how well it seals over a hose barb.I have another chamber (ablaze) that I picked up used and with the pump pumping on the closed valve it gets down to 4 torr or so (The pump itself gets down to 60 microns). With the valve open on the chamber it is roughly the same 4 torr. With the intake closed, the chamber can go a couple days before it looses 1" of vacuum, but the closed off hose will leak up in less than a minute. With the BVV chamber and the HVAC fittings, I can get down to a couple hundred microns pumping on the closed valve and the chamber will get down to less than 1 torr with the valve to the chamber open. The hose (when isolated) will also hold its vacuum for hours instead of minutes. If you need a high vacuum don't even consider a chamber that uses hose barbs.UPDATE:After reaching out to BVV and trying some initial troubleshooting, BVV sent me a new lid/gasket. All I can say is WOW. This is what the chamber should be capable of. The chamber now pulls down to 380 microns which is very good. Even more impressive is how well it holds vacuum. After letting the new lid and gasket outgas for a couple hours I pulled down to full vacuum and sealed the gauge. (I don't have a vacuum rated valve so it lets a little bit of air in until I can plug the end) The chamber now holds vacuum _VERY_ well. It went from 420 microns to 560 microns over 6 hours. That is only about 20microns per hour. That is a very good number for a welded shut HVAC system let alone a vacuum chamber with a full sized lid.----- Previous review-----Now for the bad. For all its fit and finish and high quality, the chamber would not hold vacuum over time. Over 24h the chamber would lose half its vacuum compared to the cheaper chamber this is unacceptable. I always clean all the mating surfaces with disposable IPA wipes so I can be sure they are clean and I was able to reproduce the chamber not holding vacuum numerous times. I did notice something that might explain the problem. On my other vacuum chamber the silicone seal is perfectly matched to the lid, however on this chamber the seal is clearly designed for a thicker lid than the tempered glass lid. (hard to tell in the picture, but there is a lip of excess material at the edge. Because of this the seal is not tight and for lack of a better word has "wrinkles". This prevents a perfect seal with the glass. Given how good the valves hold vacuum I'm sure this poor fitting seal is the cause for not holding vacuum over time.I would be curious if the thicker acrylic lid has these same issues (assuming the thicker seal is for the acrylic lid and also used on the glass lid which is thinner)So in short if you have your vacuum pump running, it will pull 4x better vacuum than the cheaper chambers, but if you plan to turn of the pump (for a long degas for example) you will soon lose your nice vacuum due to the ill fitting lid.-----------In short this is a premium product and worth every penny if you need a deeper vacuum.