Item: GB Universal Auto Car Accessories Vehicle Door Mount Water Bottle Drink Cup Coffee Mug Holder Stand(Sold byGioia Bazaar) at Amazon.
Recently I purchased this item. I found it very useful, as it can be mounted on the door glass. But, I found more useful to mount it on the quarter glass in my Nanno. In used it mounted on the rear glass also.
Construction is quite good and the plastic is of good quality. Particularly is holder part(the arm) is strong and can be articulated as you need.
The cup- holding part or the receptacle is around 85mm in diameter(inner), and can hold a 500 ml(may be 1 Ltr - I have not tried) water bottle or a flask with ease. There is a slot- a cleft- also so that you can keep a tea cup or a bear jug(of course I do not used the latter one - you have to check that), the handle of the jug accommodated in this cleft.
While fastening it, the holder part should be placed on a good support, may be the dash board or the like.
The vacuum cup has a broader base and is reliable - will not give way when you are on the move. In any case it is better to smear the cup with little water and then fasten it for better grip.
I bought it for Rs:250, including shipping. It is for sale by other sellers for around Rs.700(!?).
I have ordered for another unit considering all these.