going on an internet search I find this one
https://shop.ukwhitegoods.co.uk/a091664-rangemaster-flame-failure-safety-device
could well be the correct one. you would have to look at the part that’s fitted and see if it looks like it
cant find official diagrams but it may well be made by rangemaster. If so the first four digits of the serial are critical for getting info. Can you double check yours
also as a forum we have to say all gas parts must be fitted by a gas safe trained engineer who can verify the safety of your complete gas installation
Dave