Sea to summit ultra sil 20l day pack red hot on the successful heels of the sea to summit ultra sil tm shopping bag the new ultra sil tm day pack is not only ultra light strong and compact but very practical and environmentally friendly made from their proprietary ultra sil tm siliconised cordura fabric the tiny palm size pack fits easily onto your key ring in a jacket pocket or purse perfect for carrying groceries on foot or on a bike and anyone wanting to reduce their environment