In white metal, a female sphinx, tip of tail rising over the centre of the back. The sphinx rests on a blank tablet, unlike the regular battalion collars which are embossed Egypt. 37.6mm wide, 23.5mm tall, two copper loops to the reverse.
This collar is described and illustrated in Churchill* page 244.

*See Churchill, C,. History of the British Army Infantry Collar Badge [1st edition: 2002, New edition 2009] (Amazon Link)