The MOD1520-841 was specifically designed to meet the dimensional requirements of AS33601. AS33601 is the standard specification for the positioning of the machined slots after the aluminum profile has been extruded. The team at Aircraft Extrusion LLC reviewed the print for the Boeing drawing BAC1520-841 and found that the center groove tolerance did not match the AS33601. This meant that there were problems with seat attachments and fittings being either too tight or sloppy. Our suggestion for a more compatible track would be 40467-11 also available in 7075-T6511 from stock .
