Much like pellet type 90, type 45 is also produced through the grinding, sieving and pressing of natural hop cones into pellets.
The difference is that the type 45 pellets are further processed, removing more of the hops green structure while conentrating the lupulin powder.
These pellets save on space and deliver a higher alpha content to the brewery. They can be used for both bittering and/or dry hopping.