A while back, I bought a supply of plastic, in-line fuse holders from All Electronics: http://www.allelectronics.com/make-a-store/item/FHP-2/IN-LINE-AGC-3AG-FUSE-HOLDER/-/1.html

They come with pigtails, and are handy to install in old radios.

The problem is that the holders break - not when you initially install them, but after time, seemingly whether the radio is operated or not.

These are spring-loaded fuse holders that accept ordinary 3AG fuses. Depending upon how the holder breaks, a hot spring or fuse could be flapping around loose inside the radio or other device.

All Electronics specializes in surplus or reasonably-priced items. These fuse holders are not marked as approved by UL, their country of origin, or a brand name.

I intend to advise All Electronics of this problem.
Doug

That is exactly the same kind of fuse holder I've seen for the past twenty or so years on aftermarket car radios and the like. And they usually break because the plastic is too soft, nylon I think. I've even had "AA" battery holders made of the same plastic break with batteries in it. I guess we get what we pay for by getting everything from China these days. Not only no quality control, just no quality at all.