A stainless banjo bolt with an M10 x 1.5 coarse metric thread, 25mm long. It is drilled through the centre and cross-drilled into the banjo eye, so fluid passes through the bolt itself while the banjo fitting is free to rotate to whatever angle suits your hose routing before you tighten it down. The M10 x 1.5 pitch is coarser than the M10 x 1.0 used on much brake hardware, so confirm the port thread carefully rather than assuming, as forcing the wrong pitch will ruin a caliper or housing. Stainless is a sensible choice for exposed positions. Always fit a sealing washer on each face of the banjo eye.