Tinkering in dad's shop while home for Thanksgiving brings back years of fond memories. Sticking with this tradition, here are some details on an updated version of the SBSBS: Hole diameter was increased to 3/8" and dropped about 1/2" further down the outer wall. The bottle was also raised about 1/2" above the base. Greater care was taken to trim excess material. The weight of this most recent prototype dropped to 2.7 oz. while performance significantly increased (1 pint to rolling boil in 8.5 minutes). Perhaps the most exciting discovery is the adaptability of the orange Gatorade twist cap to the system!