These pants aren’t hemmed at the bottom of the legs but loop inwards to continue up 4 inches. The edge is connected there to a one inch wide, elastic, high friction coefficient band that rests against the knee.

Bending the knees when sitting or squatting causes each band to remain stationary as the pant leg rides up. The inside fabric (folds easily without creasing) thus rolls out creating a new edge at nearly the same height as before.

Presto, pronto, scrolling trouser legs mean no more drafts, or displaying short or mismatched socks. See also our Ms Modesty line of scrolling skirts.
-- FarmerJohn, Oct 18 2004

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