# Control Dimension Geometry [GstarCAD 2026](Help%20System/GSTARCAD/2026/Index.md) → [User Guide](Help%20System/GSTARCAD/2026/User%20Guide/(User%20Guide).md) → [Dimensions](Help%20System/GSTARCAD/2026/User%20Guide/Dimensions/(Dimensions).md) → [Use Dimension Styles](Help%20System/GSTARCAD/2026/User%20Guide/Dimensions/Use%20Dimension%20Styles/(Use%20Dimension%20Styles).md) The appearance of dimension lines, extension lines, arrowheads and center marks can be managed.  **Control Dimension Lines** Controls the dimension line properties like color, lineweight and spacing . **Control Extension Lines** Controls the extension line properties like color, lineweight, overshoot and offset length. **Control Dimension Arrows** Controls the arrow's type, size and visibility in dimensions and leaders. **Customize Arrows** You can create your own custom arrows by defining a block. To use custom arrow, select "Use Arrow" option in the list of arrow and specify the name of the block definition. --- [Original help](https://www.gstarcad.net/help/GstarCAD_2026_en-US/detail/GUG_DIMENSION_UseDimensionStyles/ControlDimensionGeometry.html) · © Gstarsoft Co., Ltd.