As the ball is travelling down the inlane, the player flips and holds the flipper just as the ball reaches the joint between the flipper and the bottom of the inlane guide. If done properly, the ball will hit the post under the slingshot and stop so that the player can control the ball.
This is a very skillful move with a small margin of error. Flipping too early will cause the ball to continue to roll up the flipper, causing the player to make another move to get control. Flipping too late will cause the ball to fly out uncontrollably, similar to a botched post pass.
Animation credit: Dead Flip
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