The crossbar has three sizes to accommodate for varying seat widths. A corresponding size is also available for the bottom crossbar.
Size 1) 34, 37, 40cm part No. 310205-34
Size 2) 43, 46, 49cm part No. 310205-43
Size 3) 52, 55, 58cm part No. 310205-52
Size 4) 61cm part No. 310205-61
Size 5) 64cm part No. 310205-64
The top crossbar has a identification groove and is slight short than the bottom crossbar.
The bottom crossbar has no identification groove.
Important Note: the curved in edge of the Actuator Mount Lug must face up, on both top and bottom crossbars.