An Inon Power Knob gives you the control you need when adjusting the power level on your Inon strobes. Perfect for those in temperate waters as it make adjusting the power level a snap with gloved hands. The Power Knob presses onto your existing knob and is secured using a small set screw. The Power Knob is constructed of durable impact resistant Red plastic. This knob is for Inon Type 4 Strobes (Z-240 and D-2000).