A butyl polymer having improved processability is described, together with a process for production thereof. The main body has a suspension portion and a receiving groove. The lock includes an interior space that includes latches. 8, r is a number in the range of about 0. The motor control circuit is for monitoring a parameter of the electric motor that is indicative of movement of a moveable member of the end effector, and for adjustably controlling the electric motor based on the monitored parameter to thereby adjustably control movement of the moveable member of the end effector during forward rotation of the electric motor. The electric machine can be connected to the frequency converter and as result full converter mode can continue to be operated at relatively low wind speeds.