Fit / accuracy on my Ea41 is bad. Only once you have pushed the diffuser a few times on the Ea41, so that the present in the diffuser "plastic spacers" have gradually worn away and the diffuser at all on the Ea41 (more wrong than just out) fits, went reasonably.
The whole part is me personally too cumbersome and unwieldy, since very large / long.
Order Become a shorter silicone diffuser.