If you're worried that filament will wear out the release lever on your Maker Select v2 / Wanhao, you'll want this model. This model is guide/guard to prevent filament from rubbing against the side and wearing a groove in it over  time. 

Parts needed:
2 M4 x 12 screws

Installation:

Rotate your extruder motor back so that there are no wires in the way. I believe this is optional, but cannot say for certain that the guard will fit if you do not do it.
Remove any filament from the extruder block. Remove the two bottom screws holding the extruder to the x axis bearings.
Screw the lever guard onto the block using the 2 M4x12 screws
Feed the filament through to ensure a good fit.
Carefully raise your z axis to the full 180mm to ensure the guard does not scrape (it shouldn't, but better to make sure now).