Panasonic Lumix DMW-MCTZ30 Operating Instructions Manual page 16

Preparation
≥
When inserting the silica gel, bend it as shown in the illustration below
and then insert it as far as possible. If you close the Case with the silica
gel not fully inserted, the silica gel will get caught in the O-ring causing
water leakage.
≥
If the air temperature is high and the water temperature is low, condensation
may appear inside the Case. To prevent condensation, insert silica gel
(supplied) inside the Case in advance. To prevent the Case from becoming
fogged up, insert the silica gel about 1 to 2 hours before using the Case.
4
Close the buckle.
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'
Check that the buckle is closed firmly.
Do not insert the strap etc. in the buckle.
5
After you have attached the digital camera, check one more time that
no water leaks into the Case. (P14)
16
VQT4C30
-Attaching the Digital Camera- (continued)
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Silica gel