Your search for "CAPACITORS" revealed the following:
SS-400-C – Stainless Steel Swagelok Tube Fitting Cap, 1/4 in. Tube OD, 316 SS
S$8.09
Vendor: APSS Store
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SS-810-C – Stainless Steel Swagelok Tube Fitting Cap, 1/2 in. Tube OD, 316 SS
S$17.27
Vendor: APSS Store
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