Just contact Sover Wong. He'll sell you the correct cap without having to go through eBay and having to wait for something to arrive from the states.
APUG: F2AS x2, F, FM2n, Nikomat FTn
Nikkors: 18-70/3.5-4.5G AF-S DX (f/D200), 20/3.5 UD, 24/2.8 AI, 50/2 AI, 50/1.4 AI, 50/1.4 S, 55/2.8 Micro AIS, 85/1.8 K
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