Houdini Adjustable Arm 18 Deep Glide Track(top - arm only). Position indicators for both height and tilt. Soft-touch wheel allows convenient, stable, one-hand tilt adjustment. The 27" (bottom - tray only) thin platform is for the use with keyboard and mouse. It is versatile in that the user can use the mouse on either right or left by just sliding the keyboard right or left. Comes with a removable WristRest. 

Available with "cut corners" for use in corner workstations; no additional cost. See Details. 

Houdini offers Lift-N-Lock height adjustment, Thin-Glide track, 360° swivel 
Height Range: 3" Above to 5" below the worksurface (8 in) 
Tilt Range: -20° to +10°