Blade Base: Fortress Base
Weight: 5.6g plus up to two 1/4" Metal Balls (1.05g each)
Holds two One Gram Steel Balls, one in each pocket, which move outward at higher RPM and inwards at lower RPM, intended to increase Stability and Spin Time in each respective mode.
Recoil-laden and aerodynamically abysmal design, with bad LAD to boot.
Not as heavy as its predecessor (SG Metal Ball Base), but heavy enough to weigh down any Attack shaft that may be used with it.
Able to fit a wide range of shafts and tips, but its properties make it outclassed with all of them.
Furthermore using any SG other than SG (Grease Ball Version) with any Wide Weight Disk means the balls can exit the pockets, potentially messing up the balance of the combination, further limiting any potential use for offensive customizations, and posing a serious hazard of projectile injury. As such, this is generally best considered illegal.
Bad LAD and Recoil prone shape mean that its has very poor stamina, and the limitation to two Metal Balls means it is actually slightly lighter than Customize Grip Base + Defense Ring, meaning there is little reason to use it with SG (Bearing Version 2) Shaft or Customize Grip Base Tip combos - and usability with both of these is worsened by the aforementioned issue with Wide Weight Disks.
Pretty much useless.
Fortress Base can fit up to 2 1/4" Balls.
2 Balls is generally preferred, however, if using an SG other than SG (Grease Ball Version) with a Wide-type Weight Disk, no balls may be used as they can exit the Beyblade while spinning, presenting a safety issue.