Top: shabby 敝 (.. when the cloth 巾 broke into four small pieces due to strikes 攵), below: two hands 廾 (twice this hand 屮 with the fingers 山 towards the top; side by side & simplified)
Mnemonic
If the fabric is broken up into four small pieces by strikes, the two hands have caused a damage.
The radical nobun shows a hand or 又 that holds a stick ノ (simplified from the Chinese radical 66 攴 for whip or rap. In this radical, the stick 卜 in the hand 又 is easily cognizable.)
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