Content Creation 2

I need 23 single content pages written for 4 micro niche sites. Content pages are information product descriptions that should contain origin, uses, benefits etc. as the sites do not sell anything specifically and need to be between 380-500 words. It is understandable to have content be redundant but needs to stay unique with good keyword density. I will give you the topics which I would like to have material written for once project is accepted