| 摘要 |
This detachable visor is characterised in that it consists of two superposed plastic layers 4, 5 of the same shape which are welded together along their edges 6, the upper layer 4 being made from polyvinyl chloride and the lower layer 5 consisting of expanded (foamed) polyvinyl chloride without a backing, these layers also being welded together along the marginal portions 7, 8 bordering each of the slots 3 via which the side arms of the spectacles pass. <IMAGE>
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