A tool for what job?
Measuring stuff - a tape measure or a ruler
Fitting fixed quarter light glass - string/parachute cord.
Slightly aside, but interesting:
I can't remember the technical terms for the two types of seals (Googled!), but the correct way of fitting automotive glass is:
If using the Claytonrite type seal with a locking strip you should fit the seal to the car then fit the glass by easing the rubber over the glass (no string!)
If using the 'direct glazing' type seal which doesn't have a locking strip, you should fit the seal to the glass and then use para cord/string to fit that to the car, pulling the cord from inside the car.
Edited by GraemeC, 20 October 2020 - 10:08 AM.