A 3D Model Momentum articulating arm with keyboard tray and swivel mouse tray. It is a Richelieu part number 5007438C1.
Created as part in Solidworks 2017 with 5 configurations for extended and retracted positions. The steel mounting track is 19'' long, the keybord tray is 20'' x 9.5'' and the mouse tray is 8'' diameter.
Model dimensions are 1:1 (99.%) scale taken from actual product. Several formats available for convenience.
*Model detail is what you see in the renders.