Aeron OPTIONS Compass - Horizontal rail, behind the exterior tile Aeron - Waterfall front edge Aeron - Tilt adjustment and limiters Aeron - Arm side-to-side adjustment Aeron - PostureFit lumbar Aeron - Classic Pellicle Aeron - Arm height adjustment lever Aeron - Tuxedo Pellicle Sizes: A - Small B - Medium C - Large Lumbar: AJ - Standard PJ - Posture fit Arms: N - No Arm W - Upholstered F - Leather armpads Tilt: 1 - Standard tilt 2 - Tilt limiter 3 - Tilt and seat Casters: BB - Carpet GF - Glide C7 - Hard and carpet C9 - Breaking