That’s sikaflex, Julian. It is a marine grade silicone sealant, but it’s also an excellent adhesive and is highly uv stable. There are similar “unbranded” alternatives but they are not as good. You can buy the solvent but it’s quite expensive. Before the sikaflex has cured, white spirit is an excellent solvent (ie for cleaning up immediately after the job).
Charles Erb CC19 #86 Aurora
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