--- title: "Tighten" url: "https://help.maxon.net/c4d/en-us/Content/html/MHAIRMATERIAL-HAIRMATERIAL_GROUP_TIGHTEN.html" section_path: "Simulate Menu > The Simulation System > Hair > Hair material > Hair Material > Tighten" element_id: "MHAIRMATERIAL" group_id: "HAIRMATERIAL_GROUP_TIGHTEN" description: "This Hair channel analyzes all existing waves and curves and amplifies them (negative Tighten values will relax the hair). Hair that is completely …" --- ## Tighten ![Image: 005236.jpg](https://help.maxon.net/c4d/en-us/Content/Resources/Images/005236.jpg)\ The **Tighten** channel will amplify existing waves and curves, and straight hair will curl. This Hair channel analyzes all existing waves and curves and amplifies them (negative **Tighten** values will **relax** the hair). Hair that is completely straight will be curled in the direction of the root. ### Tighten Parameter ID: `HAIRMATERIAL_TIGHTEN` · Range: [-100..100%] Use this setting to adjust the strength of the curl. Don't forget that negative values will **relax** the hair! ### Variation Parameter ID: `HAIRMATERIAL_TIGHTEN_VAR` · Range: [0..100%] Use this setting to randomly vary the strength of the curls within this channel. ### Amount Parameter ID: `HAIRMATERIAL_TIGHTEN_AMOUNT` · Range: [0..100%] Use this setting to define the percentage of hairs whose tightness should be affected. ### Curve Parameter ID: `HAIRMATERIAL_TIGHTEN_CURVE` ![Image: 005237.jpg](https://help.maxon.net/c4d/en-us/Content/Resources/Images/005237.jpg)\ In the example above, **Tighten** was adjusted to make each hair curl in the center. Use this curve to define the tightness along the length of the hair. ### Texture Parameter ID: `HAIRMATERIAL_TIGHTEN_SHADER` A texture loaded into this field will affect the tighten strength across an entire area.