Adjustable length and feather angle. The Length-Lock paddle is fastened in the middle with an easily adjusted screw on plastic collar. To change the paddle length or angle, loosen the collar (a turn is all it takes). Using the calibrated grid, line up the feather angle between the red marks, set your length (10cm of adjustment) and tighten the collar. Changing the setting or breaking it down for travel is easier than opening a twist-cap jar. Special made Epic spanner is provided for those who tighten too much by hand to loosen and dismantle.