Perform a back squat with your hands in your jerk grip width. Accelerate maximally from the bottom all the way through the top, immediately driving the bar up off the shoulders and moving the feet out to perform a power jerk.
 
This is a way to encourage more upright squat recovery posture and better acceleration. It can be used as a warm-up for back squats, especially when jerks are in the same session, or taken heavier to train and reinforce squat posture and acceleration. The power jerk variation will generally need to remain lighter than split, but will also force more speed and bar elevation.
 
Note that this is NOT a back squat + power jerk behind the neck—it’s a single continuous motion.

Purpose
The back squat – power jerk behind the neck is usually a warm-up or primer exercise for jerks later in the training session. However, it does demand ideal posture, balance and acceleration out of the squat, so it can be used as a way to train that for the squat as well.
 
Programming
Sets of 2-3 reps are appropriate at up to 70% of the athlete’s best power jerk or so.