To suit the Square end axle tube. This set will service either the front or the rear of the car 

Triumph TR2 from TS5443

Triumph TR3 to TS13045

Front or Rear Drum Brakes - Lockheed

TRIUMPH   

Triumph TR2   (Front or Rear)     (Measure Rear Brakes)      (1953- 55) 

Triumph TR3   (Front or Rear)     (Measure Rear Brakes)      (1955- 57) (** To Ch.  TS13046)

If you're fitting these on the Rear YOU MUST MEASURE the inside drum diameter because they had either Lockheed 9" or Lockheed 10” rear brakes. These are only for Lockheed 10" Brakes