How to pitch your startup to an investor in an email

How do you pitch your startup to an investor in an email? As you know, one of the popular ways of conveying information is by email, or sometimes letters are even sent on paper. So how do you convey the essence of your startup to an investor in such a letter? I recommend keeping the structure of this letter exactly the same as for the short message via a messenger, WhatsApp and so on, which I talked about above. But if you are sending a letter, you have the opportunity to make it longer than a short message and to add some charts, images and so on to the text that will make your information easier to understand. At the same time, keep in mind that practically no one reads letters longer than one to one and a half pages. So you have room for more detailed information of one and a half pages at most.