|Transparent Fluorescent Green
Colour-ID: 49 (Colour palette)
Transparent Fluorescent Green (Colour-ID: 49), colloquially known as neon green, is a colour for transparent LEGO elements. The first parts molded in this colour were introduced in 1990 as part of the LEGO Space sub-theme M-Tron. The colour is still in use today.
It should be noted that this colour is actually yellow chartreuse.