Aldi Crofton Ceramic 15 cm Knives:

These are a very good buy at $5.99. You never know when you will need an undetectable weapon. I bought several. Hard to resharpen though. A good beheading size too, I thought. They come extremely sharp (You CAN shave with them) and they will not rust or deteriorate if you leave them in a drum up the bush, in your fishing kit, in the car glovebox, etc. I should think everyone needs several; if we buy them all up there will be none left for the Jihadists: http://www.goldcoastbulletin.com.au/news/crime-court/ceramic-knives-on-sale-at-aldi-cannot-be-detected-by-security-scanners/story-fnje8bkv-1227388723382