1) 3313-4313 Rear two (72 Mark 1) 4213-3213 Units 3079 & 3179 were overhauled at Eastleigh Works. With no cab windows and new cables leading into each other. The AIT (Asset Inspection Train) was to replace the Track Recording Train (1960 Stock DMs and 73 Stock T) which is currently in use. However, in July 2021 the AIT was scrapped at LKM Recycling Sittingbourne. References External links Transport for London - Rolling Stock - 1972 Tubeprune - 1972 Tube Stock 1972 Metropolitan Cammell multiple units Train-related introductions in 1972