Hi Jewel, I actually think the plastic jar may be more durable than glass as it won't shatter from that car going over the bricks. If it's burried then the UV light that often causes plastic to deteriorate won't be a problem.
But I do worry about water getting in the jar, I'd use some silicon calk around the cables where they go through the jar and the lid to form a watertight seal. A coating of that same calk on the clamp joint wouldn't be a bad idea either. Tom Fowle
