This adapter has 18x1.5mm male threads on one end to fit the inlet of the Bosch "044" High Output Fuel Pump (Part No. FS FP044, sold separately). The other end is the correct size and shape to accept the Fuel Safe ASA 5700 Fuel Filter (Part No. FS FSHP, sold separately). This setup is only used when the pump is submerged in the tank. It is not used when the pump is installed outside the tank. Color may vary.