Double ended VS Single ended

Both types of dreads are braided into the hair in much the same way. The biggest difference here is how much thickness and how many dreads are installed into the head. 

With double ended you have two dreads installed into the hair per section. 

With single ended you have one dread installed per section.

If you want medium volume you can mix half and half single and double to get a volume of dreadloc that suits your preferences.