> For the complete documentation index, see [llms.txt](https://help.depence.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.depence.com/depence-construction/firework/build-custom-effects/tail.md).

# Tail

The tail is a particle emitter who emits particles in every frame to create characteristic tail effects. A Tail can be a child of a [Shell](/depence-construction/firework/build-custom-effects/shell.md) or [Star](/depence-construction/firework/build-custom-effects/stars.md) object. 

<table><thead><tr><th width="276">Property</th><th>Description</th></tr></thead><tbody><tr><td>Firework Color</td><td>Pre-defined colors.</td></tr><tr><td>Custom Color</td><td>Once the Firework Color is set to Custom, a RGB defined color can be used.</td></tr><tr><td>Lifetime</td><td>Total lifetime in seconds.</td></tr><tr><td>Lifetime Random</td><td>Randomization of the Lifetime in %.</td></tr><tr><td>Enabled</td><td>Enabled the emitter.</td></tr><tr><td>Emit Count</td><td>Particles per Frame.</td></tr><tr><td>Velocity</td><td>Output velocity in m/sec.</td></tr><tr><td>Spray</td><td>Random output direction in °.</td></tr><tr><td>Mass</td><td>a factor on gravity.</td></tr><tr><td>Air Resistance</td><td>Air resistance factor.</td></tr><tr><td>Radius</td><td>Particle Radius (WS).</td></tr><tr><td>Min Pixel Radius</td><td>Minimum Size of the particle in pixel.</td></tr><tr><td>Fade In</td><td>How long the particle fades in (% on lifetime).</td></tr><tr><td>Fade Out</td><td>How long the particle fades out (% on lifetime).</td></tr><tr><td>Blink Frequency</td><td>Blink/Strobe frequency in Hz.</td></tr><tr><td>Blink Amplitude</td><td>Blink/Strobe Amplitude in %.</td></tr></tbody></table>


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