Montane mens fireball jacket created for lightweight climbing and backpacking the fireball jacket provides highly packable insulation which will barely be noticed when stuffed in a rucksack its gossamer weight is achieved through the use of tough low weight nylon pertex quantum low bulk and low weight primaloft silver eco and through the minimalist yet functional design of the hood sleeves and pocketing the fireball jacket can be worn as an outer shell in cool dry conditions or as a