Two comments on these Dehydrator Plugs, and I see by the others submitted that everyone else has experienced the same problems. 1. Arrived already pink. 2. The threads are absolutely terrible. I could only get about 1/2 to 3/4 of a turn on each plug. I didnt have an 18mm die to chase the threads so I wasted way too much time messing with a jewelers file on each one before they would fit. And yes, my regular Champions will screw in by hand all the way to the copper gasket, so its not a case of dirty threads. Absolutely no quality control on these very marginal items two stars are generous. Richard B.

I like using these if Im doing maintenance on my airplane that might take several weeks to complete. The plugs are easy to regenerate at low temp in a toaster oven (I remove the silica gel to regenerate and then pour it back in when done). The units do not thread in very well, though - even on a new cylinder. Seems like I might get one thread or so engaged, but that is good enough to work well (doesnt seem to have a significant leak that causes fast deterioration of the desiccant.

fragile. hard to thread in and out. use at your own risk!

The dehydrators arrived in individual small plastics bags. The silica had all turned pink, ie, moisture saturated. Sent complaint email to Spruce - got no response. Threads are not quite right - unable to get but 2-3 turns of plugs into cylinders.

Just what I needed for the time between installing the exhaust on my experimental aircraft and first engine start. Gives some peace of mind as the clock ticks.

Plugs work fairly well, only they dont screw in as easy as they should. I had mine in my engine for a year, and the silica slowly turned pink showing they were absorbing water vapor. It only took one hour in the oven to bring back the dark blue color....ready for use again. They are kind of fragile...handle with care.

I have to agree with the negative reviews here: Ive broken two of them already by brushing or bumping against them while working on the engine. They shatter and silica goes everywhere. I also moved them all to the lower plugs because I was worried about them breaking and most of them fill with oil on the bottom. The rubber seals that holds the sintered screens in place tend to be loose and undersized so that when you take them apart to change the gel, the screens are hard to keep in place. Again, I can see the screen failing to do its job and gel falling into the cylinder. Going to replace these with Mil Spec plastic assemblies.

While this product does its job, it is so fragile that risk of breakage is unreasonable. Changing the dessicant requires removal of the plug, which is made of plastic. The glass globe which contains the dessicant is held on by a flimsy clip, over which you have to set a plug socket wrench to install or remove. So far, Ive broken off one base in the cylinder head, and broken one globe. At the very least, the globe needs to be made from shatter resistant plastic. The retaining clip mechanism needs to be re-designed, and the threaded base should be made from metal.

Received with crystals already pink. Item on backorder for several weeks.

The design could be a lot better. Its like it is from the 1950s. Glass tube, which can break if the socket slips or the fit is tight and it gets torqued on. They are hard to reassemble after replacing the desiccant. Especially when you have 12 to do. A better design would be a clear plastic tube with threads on either end and perhaps even a metal threaded base to screw into the spark plug hole.

Threads are too tight for O-200 engine. I can only screw them in part way, and the rubber seal does not seat.

I dont give the 5 stars only because my A&P had a little trouble installing them due to the rubber part doesnt turning easy. My husband had those installed years ago in another engine and he didnt have trouble. I dont understand.

Used this dehydrator plug to replace the ones that came with the Tanis kit. Far superior quality, easy to refill dehydrator with fresh desiccant when needed. Definitely recommend this for engine preservation.

Very poor thread fit between bushing and desiccant plug. Only slight side pressure will result in the plug pulling out of bushing. Not sure why this should be a challenge, but very disappointed.

Very hard to screw into cylinder. Desiccant was pink when I received the plugs. Put desiccant in oven overnight to dry it out.

The ones I purchased many years ago are great. No problems screwing them in the spark plug holes. I dont know about the latest versions and the present day quality control. The main things Im disappointed with is, the lack of parts for them especially the rubber gaskets, as they dont seem to last especially when exposed to oil.