as big as you want it to be
Your best bet is to check with your local LEO. Some jurisdictions differ. Usually, 4" is about the max.
In order for a lock-back knife to be the legal size, the blade cannot be longer than seven inches. However, carrying a lock-back knife in public is still considered illegal regardless of its size.
search the interwebs and find out
6 inches
It can be open carried, but cannot be concealed because it is a fixed blade. You will get stared at and may be harassed by police and people, but it is entirely legal. The knife must be in complete view; even a shirt or jacket hanging over the handle can be contrived as concealed.
a 7 inch blade
4 inches
A jackknife is a type of folding pocket knife that has a blade that folds into the handle when not in use. It is commonly used for various cutting tasks and is convenient for everyday carry due to its compact size.
It is my belief that one must be at least 18 years of age to purchase any size or type of knife or blade in the state of Texas.
Yes, butt it has to be under size dictated by your state.
Folding drafting tables come in a variety of sizes. You will have to find the size that suits your needs.
A legal envelope will be 4 1/8" by 9 1/2". This is so that a normal size piece of paper will fit in to it by merely folding the sheet into this rectangular envelope.
The average cost of a folding treadmill is from 600$ to 1400$ depending on brand, size, and model.