This is where armour kits being withdrawn from the regular catalogue end up. Alongside the kits themselves – tracked and wheeled vehicles – the odd detail item lands here too: masks, etched sets or material that belonged with a particular diorama.
The composition changes irregularly and follows no complete line, so the only sensible way through is to read the whole list rather than filter it. On the upside, detail sets for a previous generation of a kit are exactly the sort of thing that stops being listed and then turns out to be what you needed.
The systematically sorted range by scale is in military vehicle model kits, and upgrades from tracks and wheels through to etched grilles in armour detail sets. With armour the result stands or falls on the surface, so plan for pigments and earth tones from the start; without weathering even a precisely built tank reads as a toy. The remaining withdrawn items are in clearance.