BSP Thread: British Standard Pipe Thread
BPCA6-1     Pipe 6mm ID,   01=1/8"BSP Male Thread OD≈9.5mm                            BPCA8-1     Pipe 8mm ID,   01=1/8"BSP Male Thread OD≈9.5mm

BPCA6-2     Pipe 6mm ID,   02=1/4"BSP Male Thread OD≈12.5mm
BPCA8-2     Pipe 8mm ID,   02=1/4"BSP Male Thread OD≈12.5mm
BPCA10-2   Pipe 10mm ID,  02=1/4"BSP Male Thread OD≈12.5mm