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: F5, F3HP, F2AS, Nikomat FT2, FTn, Nikkormat EL, FT
Nikkors: 18-55/3.5-5.6G AF-S DX (f/D2x), 20/3.5 UD, 24/2.8 AI, 50/2 AI, 50/2 H, 50/1.4 S, 55/2.8 Micro AIS, 85/1.8 K, 180/2.8 PC
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