This cap will not stay on but I was able to resolve the problem by placing a couple layers of electrical tape over the "blade" part that is supposed to slip into the OBII port. Before adding the tape it fell off with the slightest brush of my pants or hand. It would be nice if the raised letters on it were painted white or red so that it would be sure to be noted by anyone removing it. As it is, I'm afraid a mechanic would just pull it off and hardly notice that it says "Do Not Flash" on it. Too easy to miss as the lettering blends write into the rest of the cap. (PS I'm writing this review again since you changed the first one to something I didn't write...please don't change my reviews again in the future :-)

The OBD do not flash cover fits perfectly on My 2011 F550 definitely will help keep dust and grime out of the connector! Nice quality! Thank you Amy and Dan another fine part from SPE .

Works as it should and Fits like a glove .

Doesn’t stay on.

Works as advertised. I just want to have it in the glove box for when I have the car serviced by someone else.

I like but would love it if the letters would stick out. Like white letters on the black plug. It is very hard to read, and I will bet a dollar if a tech pulls it off, they will not see what it says.

Fit perfect, fast shipping!

Did exactly what it was designed to do. My order was processed in a timely fashion and I received it in just a few days

I never look at reviews. I don't ever go off what some other dude says good or bad. I'm still waiting on my $2000 worth of other stuff I bought months ago to ship??? I rated these 2 products that showed up today 5 stars because SPE so far has been good stuff. When I get the 10 other things I ordered I will put it all on at once and let the SPE Universe know. Other than a 6.7 short block, full tranny or new turbos I have either already installed or waiting to install EVERYTHING on SPE's website for the 6.7 So like Roman Reigns says on WWE....Acknowledge Me!