Version 2 is got two circles. One at top and one at bottom of guide. Basic guide upgrade.
Ver 5 Has plenty of room for filament to move back and forth as printer moves in all directions. Also makes no sounds (clicking or rubbing from filament as it moves around. Add supports.
Added Version 6 with filament filter add on.
I put filament in filter first then add filter sponge. I pushed sponge in with my scrapper.
ver 6- shortened height 1/2 mm. I was told it was a little loose.It might be variation in metal when made by WANHAO. Mine fits perfect. Let me know if you need it bigger or smaller.