2012-2015 Mercedes-Benz ML350 Roof Racks

What's the difference between Solid vs Click-In Crossbars?

SKU	Name	USD
8-00-9663-BK	EXR 'WEEKENDER-9663' Black Crossbars - (2) 48" Solid bars, 2.46" above Rails	488.35
8-00-9766-BK	EXR 'WEEKENDER-9766' Black Crossbars - (2) 51" Click-In bars, 2.46" above Rails	745.39
8-00-9766-RD	EXR 'WEEKENDER-9766' Red Crossbars - (2) 51" Click-In bars, 2.46" above Rails	855.31
8-00-6667-BK	EXR 'CAMPER-6667' Black Crossbars - (3) 51" Solid bars, 2.46" above Rails	862.79
8-00-6767-BK	EXR 'CAMPER-6767' Black Crossbars - (3) 51" Click-In bars, 2.46" above Rails	1080.89
8-00-6668-BK	EXR 'OVERLANDER-6668' Black Crossbars - (4) 51" Solid bars, 2.46" above Rails	1159.55
8-00-6767-RD	EXR 'CAMPER-6767' Red Crossbars - (3) 51" Click-In bars, 2.46" above Rails	1245.77
8-00-6768-BK	EXR 'OVERLANDER-6768' Black Crossbars - (4) 51" Click-In bars, 2.46" above Rails	1450.35
8-00-6768-RD	EXR 'OVERLANDER-6768' Red Crossbars - (4) 51" Click-In bars, 2.46" above Rails	1670.19