as opposed to "fully open gusset" - с полностью раскрывающейся горловиной

https://www.tylerpackaging.co.uk/products/conventional-flat-...

Single Lip/ Reduced Gusset

Offers better shelf presentation than fully open gusset, enables a variety of resealable closures to be available, and can include our Easy Open feature for consumer convenience

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Note added at 8 hrs (2022-11-07 02:11:03 GMT)
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Возможно, под «single lip» здесь имеется в виду, что пакет сконструирован и сварен так, что двойная кромка бокового фальца ближе к горловине переходит в одинарную, благодаря чему горловина сужается, а образовавшееся отверстие становится более удобным для наполнения и использования, чем у более простой конструкции, напр. fully open gusset

https://www.packagingconnections.com/news/single-lip-bag.htm

Single Lip Bag

The new bag, which is the only one of its kind in europe, offers a number of benefits, from how easy it is to implement on the production line to how practical and simple it is for users to open.the bags first unique characteristic is an added flat bottom, which ensures that the bag takes its shape instantly and makes it possible to optimise filling rates and significantly reduce waste on the packaging line. The second benefit is a lateral gusset that is carefully cut, providing complete waterproofing and conservation over time thanks to the inert gas used in the packaging process. This same cut on the gusset also means that users can open the bag simply and easily. Finally, the new bag provides unparalleled visibility and legibility of the brand name, as well as allowing companies to offer products that always arrive completely fresh.

https://globalpetindustry.com/sites/default/files/2020-04/El...