A long-lasting and effective pheromone used to trap spruce grouse. Package contains 5 ampoules. The ampoule is ready for use as soon as you open it. If the ampoule is punctured or broken, the time of action is considerably reduced. The unused ampoule must be stored in the freezer (not below -18C). The active substance will keep for at least 2 years if stored in the freezer.