This barlow lens features a twist lock mechanism which makes your eyepiece/camera centralized. This makes more of the stars focused so it is far better for astrophotography. Objects that are in the center of the field are more likely to be pin points.
The RVO x3 barlow lens is a high quality fully multi coated lens with integrated t threads for attaching cameras directly to the top. The barlow lens is even filter threaded for attaching your favourite 1.25" filters.