The T profile has an upright web topped by a horizontal flange, so its section matches the letter T. On a model it is used for beams and frames that need a flat face on one side and a projecting rib on the other, and also for edge trims, guide strips and structural members of buildings.
Against an angle it carries the flange symmetrically to both sides, which gives a different silhouette and, more noticeably, a different shadow along the length of the part. A T is worth buying ready-extruded exactly where the flange has to stay square to the web over a long run, which is what it is wanted for in roof members, bridge girders and shop-front framing. The other ready-made sections, angles included, are in plastic profiles and sections, and the strip and rod used alongside them in styrene square rod and strip.
