There are many resins in use by climbers for installing glue-in bolts and Hilti RE500 epoxy resin is but one of them. Hilti RE500 is a premium performing epoxy that will cure underwater, designed for high strength in smooth holes (diamond drilled in the construction industry), has long term stability and capable of resisting very high loads.
The vibrant colour of freshly mixed RE500 is sometimes cited as a drawback or issue associated with using this particular resin. The reality is that over time, the initial red colour fades, and with it fades the relevance of colour.
Some snap shots of recently installed bolts with RE500
RE500 resin a month old and yes; that is an inverted resin bolt placed in a roof with this epoxy.
RE500 resin 3 – 6 months old. The initial vibrant red has faded rapidly to a light brown colour.
The resin colour continues to fade further beyond 1 year.