The one that Parts Express sells is solid brass internals with o-ring seals and is waterproof. It accepts AGU glass fuses and #4.
(#070-660) It accepts stranded.
Using #2 with the AGU isn't the best idea since the AGU is only capable of a reliable 60A continuous. With #2, we'll assume you're looking for more than 60A.
To handle the current that will flow on a #2 (if you really do need #2) , you are better off using a wafer-type fast-blow fuse with crimped and/or soldered copper lugs.
(#263-630)
Both are well constructed and take heat with no problem.
A word about materials from Graingers: Although they are very well constructed, these are mostly for high voltage use. The fuses that fit most of these fuseholders are designed for interior use. The fuse's current ratings are also rated for AC current. Also, if you are working on an OEM application or will be installing in a new vehicle, note that most of these "industrial" components carry no type of certification for mobile use such as DOT or SAE- which can be quite important if you are dealing with a $700,000 ladder truck or command truck and it burns up (even if not caused by your install).
We hate to have to think of things this way, but if this would happen and an insurance company discovers you used a non-approved fuse or component in an installation that carries 140 amps, guess who has a problem whether or not they caused the damage?
Cover You Ass!
Some stereo components aren't SAE/DOT approved, BUT....they, at least, are high quality components designed for 12 volts in a mobile application.
http://www.partsexpress.com
also, call TST. This company makes many 12 volt componets used by most OEM manufacturers.
TST- 1-800-428-4449
The TST units would be the best, although more $$