Your search for "tubes" revealed the following:
SS-600-3 – Stainless Steel Swagelok Tube Fitting Union Tee, 3/8 in. Tube OD, 316 SS
S$44.63
Vendor: APSS Store
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Brooks Instruments 1350G & 1355G Glass Tube Variable Area Flowmeters (Rotameters)
S$1,700.00
Vendor: APSS Store
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V-774-Q: Pop-A-Plug® CPI/Perma Heat Exchanger & Condenser Tube Plugging System
S$0.00
Vendor: APSS Store
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