Torque wrenches 3/8 and 1/4 drive
Ive been looking at Torque wrenches and I´m kind of puzzled.
When reading about it on the Park Tool website I come across this: The "TW-1 is 1/4" drive (includes 3/8” adaptor) and ranges from 0-60 inch pounds with compatible metric equivalents. "
What does 1/4 and 3/8 drive mean?
I tried to download the instructions but it said the document was damaged.
Any help?