Chamfers or fillets on outside edges?

Sharp edges need to be broken for safety and to avoid damage. How you specify it changes the cost.

Edge break note

For most edges, a general note such as Break sharp edges 0.2–0.5 × 45° is enough. The machinist deburrs by hand or with a chamfer tool and no modelled feature is needed.

Chamfers

A 45° chamfer is made with a standard chamfer mill that most shops keep in the machine. One tool handles many sizes.

Fillets

A rounded outside edge needs a corner-rounding cutter of exactly that radius, set up precisely to avoid a step. Several different radii mean several special tools. Use fillets where they matter for looks, handling or stress, and keep to one radius.