Sill to 'B' post Strengthener flat plate Left hand and Right Hand for TR4, 4A. This flat triangular shaped plate along with its stiffener 611571 or 611572 is welded to the sill and the 'B' post on the seam so that that the furflex can run from the sill to the 'B' post. On these cars the door seal follows another route, in a channel on the sill and the 'B' post.

This system is poor. the furflex leaves a triangular mark on the door card and the seal in its channel ensures early rotting. A better method is to use the TR250,5 and TR6 approach of welding the stiffener further inboard and using a combined seal and furflex. The correct parts for this are 621715 and 621716.

It is worth noting that Triumph carried the part numbers and drawings for the the TR4 and 4A strengthener over to the TR250, 5 and TR6 parts books which are completely wrong for the later cars and will not work at all. This spectacular mistake was carried on right through to the 1974 TR6 parts book thus perpetuating the error for a full 8 years.  

For reference the incorrect part numbers in the TR250, 5 and TR6 parts books are 611570 for a flat plate and 611571 and 2 for the LH ans RH 'top hat' stiffeners respectively. 

This part appears on the following Triumph Catalogue Plates