What they say:

A simple and reliable twist-to-inflate system, the Windstream Twist inflator head works with all 3/8 threaded inflation canisters but with a twist. With no spring on the head, air flow is controlled by twisting the cartridge rather than pushing. Auto seals when not engaged.

• Compact, lightweight design fits in tight spaces
• Press-on for both Presta and Schrader valves
• Compatible with 3/8 threaded cartridges
• Rotate CO2 cartridge to regulate inflation
• Kit includes CNC-machined aluminum inflator head with green finish for better visibility
• One 20g CO2 steel cartridge