ðɪ ˈɔːɹdnəns dᵻpˈɑːɹtmənt hæd ɔːlɹˌɛdi bˌɪn wˈɜːkɪŋ ˌɔn ɐ hˈɛvili ˈɑːɹmɚd ˈɪnfəntɹi tˈæŋk dɪzˈaɪn fɚðə bɹˈɪɾɪʃ, jˈuːzɪŋ ˈɛm fˈoːɹ pˈɑːɹts.
The Ordnance Department had already been working on a heavily armored infantry tank design for the British, using M4 parts.