Ruler
Definition
A ruler is a flat, hard ruler (usually made of wood or plastic) that is used in BDSM as a striking instrument for sharp, direct, and linear pain stimuli. It functions as a variant within impact play, comparable to light canes or flat paddles.

Explanation of ruler
The ruler is often used because of its accessibility and the specific sound and feeling it gives: a quick, sharp tap that hits directly in a straight line. Especially on hands, buttocks, thighs, or the soles of the feet (bastinado), a ruler is surprisingly intense.
Because the surface is narrow and the stroke bends very little, the pain feels clear, sharp, and immediate – ideal for subs who enjoy precision and discipline-associated play. The object also has an associative power: a ruler evokes school discipline and authority, so the psychological effect is often just as great as the physical stimulus.
Safety & points of attention
Pay attention to fingers and joints. The narrow edge of a ruler can quickly become too hard.
Do not use on the spine or bone edges. Too hard blows can cause damage.
Control over force. A ruler has little flexibility; light taps quickly become hard.
Related terms ruler
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