Panasonic WX-CC411 Manuel D'utilisation page 23

Use the accessory clamp to secure the power cord to the wall and attach the clamp using a screw
(4.1 mm × 25 mm {5/32 inches × 63/64 inches}).
[Minimum pull-out strength: 780 N {80 k f}]
Screw (locally procured)
150 mm to 200 mm
{5-15/16 inches to 7-7/8 inches}
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