Bottles are sent to a sorting centre where they’re separated into three different types of plastic – PVC, HDPE and PET, and then squashed together into large blocks. From there they're taken to a reprocessing plant where they’re separated into individual squashed bottles.

Each bottle is washed to remove labels and dirt, dried, then ground down into small flakes. The flakes are melted and squeezed through tiny holes, through which molten polyester emerges. As it solidifies it’s cut into small pellets which are then stretched to make thread. The thread is knitted to produce a roll of fabric, which is dyed and used to make clothes.

When clothes last longer, they can be worn again and again, which reduces the need for new clothes and creates less impact on the environment. Quality has always been one of the M&S company values, and so M&S childrenswear is made to be passed down, not thrown away. The archive collection includes children's coats from the 1960s, some with more than one name written inside, showing how long they lasted. 

This has inspired M&S designers to add special labels to kids’ coats with space for three names, making it easier to pass clothing on to siblings, cousins, or friends - a small detail with a big impact. 

M&S schoolwear goes through lots of tests to make sure it’s going to last. This includes water and stain resistance, strength and flexibility. Watch the Plan A Back to School Durability film to find out more.