This is an unopened bottle of Lauritz Bergendahl's "dyp impregnering" 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.
The blue-labeled "dyp impregnering" (deep impregnation) is used when skis are new, but I'm sure you won't get in trouble if you use it after that. 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.
