Scalable
Switches the scalability of the object on. With scalability switched on the label scale of the current section (model or layout viewport) is used to control the size of the label.
With scalability deactivated, you can specify the current scale factor in the input field.

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Opens the Dialog box Annotative scales, where you can assign scales to the leader. You will find further information in the Chapter Label Scale.

Actual text height
Specifies the actual text height. This is calculated from the current text height and the scale factor.

Layer
Activates the layer replacement. If you activate the tick box, you can change the layer set as standard.