In Java Edition, pistons finish extending early and start retracting if given a pulse shorter than 3 game ticks (1.5 redstone ticks 0.15 seconds).

Sticky pistons stick to a block only when retracting, so a block next to the piston head can be pushed aside by another piston and sticky pistons cannot hold falling blocks horizontally against gravity. A sticky piston also pulls the block attached to its head, but not any of the other blocks it may have pushed. It finishes retracting 2 game ticks (1 redstone tick 0.1 seconds) after it starts. Like extending, this retraction starts immediately in Java Edition or, depending on how it was powered, after 1 tick in Bedrock Edition. When a piston loses power, its head retracts. If there is no place for the entities to go, the block pushes inside them, suffocating mobs if the block is not transparent when pushed into the eye height of the mob. Any entities in the path of the extending head are pushed with the blocks.

The piston makes a sound that can be heard within a 31×31×31 cube centered on the activating piston. When it extends, it pushes at most 12 blocks. When powered, the piston's wooden surface (the 'head') starts extending immediately in Java Edition or either 2 game ticks (1 redstone tick 0.1 seconds) later or immediately, depending on how it was powered, in Bedrock Edition. Pistons are always placed facing toward the player. See also: Tutorials/Piston uses and Mechanics/Redstone/Piston circuits The pickaxe is also the preferred tool for breaking the head when extended. In Java Edition, it is faster to break them with a pickaxe.

A piston can be broken using any tool with equal efficiency, and always drops itself.

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