Hi, you can attach center-pinch lens cap on this filter , except the ND1000 filter , the CPL, UV and magnetic adapter ring can attach lens cap. 

Hello! If you use the magnetic UV filter separately, or use the magnetic adapter ring together with the CPL filter, you can use a normal lens hood on it. Does not require a larger thread. If you use the magnetic adapter ring together with the ND1000 filter, you cannot use another lens hood on it. 

If the filter size for your lens any of these adapter ring ( 52mm/ 58mm/ 62mm/67mm/ 72mm/ 77mm/ 82mm) then yes. 

hello , if you put a lens hood on 52mm filter, you need a 55mm lens hood 

The adapter clicks on the lens. It has a small dark gray colored lever (not the white plastic tab to change aperture), level to the outer edge of the bottom ring accessible when removed from the camera, grab the whole adapter with your left hand and push the lever in with your thumb, and while pushing, rotate the lens with your right hand to remove it. You need to push in that lever to unlock the lens.