🇬🇧X1(M5) X1(M6)Motorbike Motorcycle CARB Balance Vacuum Gauge Adapter 6 Caps.

6mm (M6) thread to a 4mm hose tail, this is a standard M6 (1mm thread pitch). 5mm (M5) thread to a 4mm hose tail, this is a standard M5 (0.8mm thread pitch).

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