outer diameter 9.5 inner diameter 7(special-purpose upper spin):11
golgi MP5 inner diameter 7 aluminum tube+upper spin:15
HQ-MP5K inner diameter 7 aluminum tube+upper spin:15
The top spin is fixed on the casing, not fixed by the inner tube, It must be inserted in the bottom.
Note: Golgi MP5 inner tube length 21.5cm, HQ-MP5K length 14.5cm inner tube.
Use the inner 7 inner tube to match the 6.9-7.1 water bullet.