This Parts breakdown is for the following machines:
NEMA L6-20 20 amp 250 volt grounding twist-lock female flanged outlet. This is the standard size used on the Hummel & Clarke/Alto machines.
$22.22
Item # 6216
NEMA L14-30 30 amp 125/250 volt grounding twist-lock female connector. 4-prong, 2 power, 1 common & 1 ground. This is used on the Clarke/Alto power booster.
$67.14
Item # 1430C
NEMA L14-30 30 amp 125/250 volt grounding twist-lock male flanged inlet. 4-prong, 2 power, 1 common & 1 ground. This is used on the Clarke/Alto power booster.
$87.45
Item # 1430FI
3 position rocker switch for the Clarke Power Booster.
$53.90
Item # A035
Here are a few tips on using them.