not friction, it has snap collars that lock into place, hence to take it out you need the finger strength of hercules to pull it off.

my old one was easy - hold fully out and one yank made it slide out, the new one with new switch. NO WAY - it required a rubber padded vise grips to remove.

__________________
2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)