@Waldrel 

You don't want to.   Rnage Extenders are half-duplex devices.  They can only communicate in 1-direction at a time.  Either to the host or to the client.  This is why your speed is up to 50% lower than when connected to the router.  By daisy chaining an extender to another extender this would effectivly make the connection unusable.  Its not recommended.  If you need to daisy chain extenders you would want to look at Mesh or even powerline as a more relaible alternative.