Hi Baltic, welcome to the forum, I bought mine when I bought the camera, I did not give it any thought. It would be interesting if someone could give an indication of the fluid life if any.
I take a lens pen with me every time, more convenient than messing with fluids. Trinity Beach is a nice part of paradise.
Nikon D7000, Nikkor 80 - 400G, Nikkor 18- 200 VR II, f3.5-5.6.