FuseFX LY-Series colours (AKA Layering colours) are sheer skin tone paints and are a vital part of creating the perfect skin tone finish. LY colours directly correspond to S-series and SFX-series base colours (eg S-301 Light Flesh colour pigment is equivalent to LY-01 Light, S-312 Howie Green colour pigment is equivalent to LY-12 Green, etc.) and thus adding a layer of LY colour over top of a layer of F-series or M-series paints will create a perfect "under the skin" look.
LY-Series paints are sold in 2-part "kits." When using FuseFX paints you mix an equal amount of "Part A" and the chosen colour, then apply as desired to the surface of your cured and clean silicone piece (to prevent loss of details you can also "backpaint" colours into a released mold before filling with the bulk of your silicone).
15 colours are currently available, in 4 different sizes: 30g, 60g (not shown), 250g, and 500g.