This is an unopened bottle of Lauritz Bergendahl's grunn-smøring/pine tar for wood skis. Bergendahl was a ski star before leveraging his name for marketing purposes - he won the Holmenkollen 50km FIVE times. Think it's hard to ski 50k? Try it on a pair of two-by-fours, which was about the level of sophistication of skis a hundred years ago. Pine tar made things a LITTLE easier.
Unlike the blue-labeled "dyp impregnering" (deep impregnation), which is used when skis are new, the red-labeled grunn-smøring is applied periodically over a ski season, or when needed to keep the bases of the skis protected from moisture. According to the instructions, heat is not necessary for application, but using a torch or heat gun will result in a more durable application.
Note that the bottle may not appear to be full; this is due to the xylene component of the product that can evaporate over time. Mineral spirits (or xylene) can be added to increase volume.
