Senior plc (LSE: SNR) is the holding company for a global group of firms in the manufacturing and engineering industries, headquartered in Rickmansworth, Hertfordshire.

The Company is listed on the London Stock Exchange and is a constituent of the FTSE 250 Index.

Senior was originally established in 1933 by a group of former employees of Green's Economisers Ltd. as a rival concern.

The company was listed on the London Stock Exchange as Senior Economisers Limited in 1947.

Source: Wikipedia