Dual Cutter with Handle

This twin parallel blade knife allows for cutting strips of
vinyl or gaps between the window seals and the window
perf for longer life window perf installs.

•With twin parallel blades, this knife allows for cutting strips 3mm to 16mm through different mediums.

Made In USA. Replacement Blades available.
Product Review by Gerald Voigt
If you are constantly cutting narrow strips of tape for masking and need them precisely the same each time, then you might want to pick up this set.
I found it very easy to use, I simply set the width between the blades by holding then to a steel ruler. Or using the model itself to set the spacing such as a stripe on an airliner using decal stock.
The adjustment knob has just the right amount of friction to turn easily yet hold the blades in a constant parallel. It was comfortable to hold and use with no worries about slipping from ones hand.