Knobit is a larger acetylene torch knob that goes over your existing Smith torch knob for better single-handed control of your flame. This unit is designed and made to fit only the Smith torch style # NE180 or NE180A with the standard knob/valve assembly #L700-7.
Directions for installation: Push the Knobit over your existing Smith torch knob, it should snap and have a tight fit. You might need to exert some small force to push it in.
This Knobit is made out of Tough 3D-printed resin which should withstand normal use and high temperatures.
