I used to travel with a vibration analyzer that was purposely built to fit the sizers made to FAA specification. I would regularly be asked to check the size. It would go in, but I sort of had to wiggle it to get it to go to the bottom. When I pulled it out, if the sizer was not anchored to the floor, it might come up with the analyzer. I would ask the OA to hold the sizer down while I pulled my analyzer out. Never was denied. It went in and it came out. Test passed.