The 19198 is a 0.013 in. ID orifice that comes as an option of the 18072 TGA100A Heated Intake Filter & Orifice. The 19198 may be ordered to replace a damaged orifice or to change from another size of orifice. Swagelok® ferrules and nuts are required and ordered separately.
In the image, three tubing flow restrictors are displayed to show the restrictor from various angles.