It used a lead wire weight at tip. On surface is white PVC Shrink Tubing.

翼尖有铅条配重，表面蒙乳白色热缩膜。

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The E-PET film provides shrink curves of PVC with gloss, coefficient of friction and printability of PET and toughness in between OPS and PVC.

E-PET收缩膜的收缩曲线具有与PVC一样的光泽，具有PET的摩擦系数和可印染性，并且其韧性处在在OPS和PVC之间。

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For the 12, 000-seat basketball arena, architects at Wilkinson Eyre devised a rapidly erected steel-frame system shrink-wrapped with a white PVC skin, the curved steel stretchers forming a pattern of alternating diagonal projections on the outside.

WSJ: London Olympics 2012 | These Knock-Down, Shrinkable Games | By Hugh Pearman