The GR1 and the Rucker are very similar but do have a few differences. To begin with the Rucker and the GR1 both have molle webbing on the outside of the ruck, a hydration port for your bladder, they both open flat, have 2 internal pockets and 1 external pocket, both water resistant and both are water resistant. However, the main difference is the "Bombproof" laptop compartment. The GR1 has a laptop compartment with a false bottom which the Rucker does not have as the rucker is solely meant for rucking, where the GR1 is meant for rucking and a daily everyday bag. The Rucker also has an internal frame sheet that is non-removable, where the GR1 frame sheet can be removed.