Solidify Faces

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This takes a selection of faces and solidifies them by extruding them uniformly to give volume to a Non-manifold surface. This is also available as a Modifier. After using the tool, you can set the offset distance in the Настроить последнюю операцию (adjust last operation) panel.

Толщина (thickness): Amount to offset the newly created surface. Positive values offset the surface inward relative to the normals direction. Negative values offset outward.