The cozy vest (gilet... body warmer - whatever you want to call it!)

Made from very light, windproof and water resistant fabric with extra warm synthetic (recycled) fibre insulation. 

It's also worth mentioning that this jacket incorporates Jack Wolfskin's recycled Microguard Ecosphere synthetic fibre insulation.

• Very light, robust, windproof and water resistant ripstop fabric
• Extra warm insulation (140 g/m²) made of recycled synthetic fibres
• 2 hand pockets
• Reflectors
• Fast drying
• PFC-free
• Weight: 250 g (size 128)

We say:

A lightweight but tough jacket, perfect for school. It will keep the rain off in light showers and even if you get caught in a downpour you might get a bit damp but the the insulation will still be keeping you warm and it will dry out quickly.