Tips for Using Strerch Lids.
For optimum suction, make sure the stretch lids and container are dry. They slide when wet. However, even if they are moist, they can be used as lids, especially when cooking in pots and microwave ovens.
For storage in the refrigerator, select the cover closest to the actual size of the container. Sticking out the edges may cause them to be knocked off in time. Similarly, for this reason, we recommend that a shorter cooling cycle be used only in the freezer, rather than long-term storage in the freezer.
As with any top, when cooking in a stove, microwave or oven, the lid becomes hot and sealed in steam, so be sure to use gloves or tongs when removing the lid to avoid scalding.
These stretch lids are suitable for all smooth, rimmed containers. However, if your bowl or basin has an inverted mouth or an extended handle, you can still use them if you use a bowl or basin large enough to extend the entire edge. We found that this effect works in a microwave oven, usually with the lid still sucking when steaming vegetables, but exhausting when cooking.
If the lids extend beyond the edges at all edges, you can even use them on square containers.
Although tight suction seals are usually used, you can usually lift the container with stretch lids , but it should not be done when it is full.