The Alpha Direct 4004 Hoodie is an ultralight hoodie built with Polartec Alpha Direct 4004 fabric. Alpha Direct 4004 is the 90gsm variant. This is an excellent intense activity insulation layer that should be paired with a shell for a very light, modular system. The structure of the fabric is very open, with fluffy tufts between. With a shell to cap the air, the tufts create loft and the spaces create dead air. It keeps you very warm for it’s weight. Without a shell Alpha has very little insulation value, which is one of it’s benefits. By venting the outer shell and exposing the Alpha directly to the air, you can dump a lot of heat quickly without the need for inner layer zippers. You can change the outer shell to deal with different conditions while providing a huge and highly adjustable range of insulation. This can’t compare to a true static insulator like a down sweater at camp but it can sometimes be enough to get by with, while covering a giant range of conditions while active.
Approximately 5oz (small).