The Heavy Duty RFMPS2 roof rack system permanently attaches to your roof via rivets. Its key feature is a base which swivels to allow a better fit to a wider variety of roof shapes Includesding flat, angled and curved. Featuring a low profile design, this system is aesthetically pleasing and maintains its looks after years of continuous use.Comes in a set of 2 legs.Also compatible with Rhino-Rack Vortex Bars.