At the 2007 Rochester hamfest in June I picked up an entire box of capacitors for $65. The 4 old ones in the 900 volt model were rated at 7500 uF at 250 volts. Four in series yielded 1800 uF at 1000 volts. The new ones are 3700 uF at 450 volts. Two in series will give 1900 uF at 900 volts. My cabinet will hold 8 of them for a total of 7500 uF at 900 volts. That is 4 times the uF of the current washer launcher. Also the popularity of my coil gun has lead to me making an adapter so that the coil gun will plug into the 900 volt power supply, not just the 300 volt power supply. I can't wait to see how fast the bolts will fly at 900 volts!