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Low Pressure section does not look like the Mark 20.That's a MK20 first stage. Repair guide can be found here: https://www.divestock.com/downloads/dl/file/id/405/scubapro_repair_guide_mk20_mk25.pdf
Roland
All have 4 ports on the side and one on the top. I have 9 sets of SP MK20 G250 regs
Below is an MK15 with SPEC boot but the early MK20 accommodates these as well if you take the trim ring off
That’s something I wish they would remake!Below is an MK15 with SPEC boot but the early MK20 accommodates these as well if you take the trim ring off
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