Acid #4 is a brightened, tangerine orange with a matte finish. The texture was soft–just a smidgen powdery–and very blendable, while the pigmentation was good. This shade wore well for eight hours before showing slight signs of fading. Wet ‘n’ Wild A Regular at the Factory #3 (LE, $2.29) is a touch darker. Fyrinnae Pyromantic Erotica (P, $6.80) is more shimmery. Illamasqua Vulgar (P) is very similar. Inglot #123R Top (P, $6.00) is more orange, less yellow. See comparison swatches.