Gerber Layer description


Signal layers
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GTL: Top Layer
G1:  Innerlayer 1
G2:  Innerlayer 2
GBL: Bottom Layer

Fabrication layers
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GBO: Bottom overlay (silk screen)
GTO: Top overlay (silk screen)
GBP: Bottom solder paste
GTP: Top solder paste
GBS: Bottom solder mask
GTS: Top solder mask

Mechanical layers
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GD1: Drill layer
GM1: Board outlines
GM2: Board dimensions