1/4” hose tails are usually used with 6mm gas hose. 5/16” tails are used with 8mm hose. 3/8” tails are usually used with 10mm gas hose. The 3/16” hose tail size is used with a 5mm gas hose. 1/4” BSP hose nuts are suitable for connecting hoses to lightweight style shanks, whereas 3/8” BSP nuts are used to connect to regulators, Type 3, 4 and 5 style shanks and NM type cutters.
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