This is the neoprene cover that goes over the Clamcleat as can be seen in photo 5 circled in green. The clamcleat cover for the V4 bars sits over the clamcleat, it protects it and also helps protect you should you decide to head butt the clamcleat! The cover for the V4 bars does not contain magnets.
Quite easy to replace, if you are not sure, this video from Ozone is very good.
Pack contains one neoprene cover.