Oops, sorry - I'm thinking 44 (like a Wagoneer - the usual home for a Quadratrac), not 30. The 30 uses a flange, not a slug. See the picture above.
The 44 uses a flange that is commonly called a slug, because it has no actual flange. Instead it has splines and goes inside the hub end. Sorry for the confusing terminology. Forget about slugs.
The axle comes from the factory with flanges. Flanges are removed when locking hubs installed.
1) '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS, hubcaps. 2) '82 J20 360/T18/NP208/3.73, KOs, 7600 GVWR 3) '75 CJ-6, 304/T15, PS, BFG KM2s, soft top 4) '95 VW Golf Sport 2000cc 2D