In modern construction, studs are usually cut to exact length at the mill. they are designated by the letters
a. p. e.t.
b. e. p.t.
c. t. e.l.
d. c. t.l.

P.E.T

Explanation:

Stud is a short form of stud wall which are typically vertical framing members in a wall of a building. Wall studs are available in standard lengths but since the height of ceiling vary, sometimes one has to cut the stud walls on site to fit. Therefore, there are pre-cut studs which are more efficient  in implementation. These are usually referred as Precision-End Trimmed studs, (P.E.T). Therefore, stud walls which are cut to exact length at the mill for modern construction are designated by letters P.E.T

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