razkolnikov wrote:The adapters I found (McMasters) are around $20/each, but I may just have to bite the bullet
You could try swagelok.com (no affiliation). They have the same SS fittings for $13 ea. Or brass fittings @ $6 ea. I don't know if the shipping is comparable or not. ISO = BSP.
SS-6-A-6RT SS Adapter, 3/8 in. Female NPT x 3/8 in. Male ISO Tapered
SS-6-A-6RS SS Adapter, 3/8 in. Female NPT x 3/8 in. Male ISO Parallel
B-6-A-6RT Brass Adapter, 3/8 in. Female NPT x 3/8 in. Male ISO Tapered
B-6-A-6RS Brass Adapter, 3/8 in. Female NPT x 3/8 in. Male ISO Parallel
razkolnikov wrote:There seems to be some sort of gasket in the inlet line which might indicate it's a BSPP female
If you want to roll the dice, it's probably a BSPP fitting because of the "gasket" that you alluded to earlier. BSPP seals on the face, BSPT seals on the thread.
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