Research seems to indicate that over one-third of the tanks used by the Russians in defence around Moscow during Barbarossa (in Dec 1941) were British:
* https://www.historynet.com/did-russia-really-go-it-alone-how...
* https://www.tandfonline.com/doi/abs/10.1080/1351804060069781...
* https://twitter.com/adam_tooze/status/1344630636296818690 (via)
More from the 2013 Kursk presentation at the [US] National WWII Museum:
* https://www.youtube.com/watch?v=N6xLMUifbxQ
I've heard the expression: Word War Two [in Europe] was won by British intelligence, Russian blood, and American steel.