Lines indicating extremes of dimensions are drawn where required, and the dimension lines drawn between them perfectly placed outside the object, either to the right side or below it. For small dimensions. The arrow heads are drown to point inwards, and the figure is printed between the arrow heads. All arrow heads should be small, written properly and enclosed. Hidden details are indicated with dotted lines. Where a hidden detail is large or has complex shapes it is often preferable to have a sectionalized view in addition to or in place of usual views. Odd shaped objects should be dimensioned. Rounded corners and small diameter holed should also be dimensioned.
Leader lines for notes should be straight lines leading from a dimension value to the feature on the drawing to which the note applies. Usually, leader lines should have arrowheads at the pointing ends, and never at the note end, while the note end should terminate with a short horizontal bar.
