Hardware for VRC is given under <R7> c. Any commercially available #4, #6, #8, M2, M2.5, M3 or M4 screw up to 2" long (nominal), and any commercially available nut and/or washer to fit these screws.
<VUR2> a. i. expands this to "Small hardware, such as screws and nuts found in VRC field kits, are permitted."
Is the intent of VUR2 to allow any hardware up to size 1/4" (M6) for VEX-U? VEX-Pro does not specifically sell hardware, but some hardware is included in various components, such as VERSADROP has 1/4" and #10 hardware included. Also, Versaframe specifies #8 screws or 5/32" aluminum rivets for assembly, but VEXPRO does not sell either in the catalog. Would aluminum rivets (and any size steel screw or nut for that matter) fall under the "unlimited aluminum and steel" since both types of fasteners could be machined from aluminum or steel bar stock as allowed by <VUR-3>c?