Upvote:5
From reading Power plug & outlet Type H and Power plug & outlet Type O it appears that they are not compatible. The latter link explicitly says
Although they look similar, type O plugs are not interchangeable with the Israeli type H
Also from Israel SI32 (Type H) it says
The pre-1989 system has three flat pins in a Y-shape, with line and neutral 19 mm (0.75 in) apart. The plug is rated at 16 A. In 1989 the standard was revised, with three round 4.5 mm (0.177 in) pins in the same locations
And Thai 3 pin plug TIS 166-2549 says
The plug has two round power pins 4.8 mm in diameter and 19 mm in length, insulated for 10 mm and spaced 19 mm apart, with an earthing pin of the same diameter and 21.4 mm in length, located 11.89 mm from the line connecting the two power pins
There is a difference in the pin diameters. Depending on which way you are trying to plug things in you could potentially either jam things in or have a loose connection. There may be enough mechanical play to do this, but I would not recommend doing it.
And I love this quote from the World Standards website (above)
Type H plugs are among the most dangerous ones in the world: the prongs are not insulated (i.e. the pin shanks do not have a black covering towards the plug body like type C, G, I, L or N plugs), which means that if a type H plug is pulled halfway out, its prongs are still connected to the socket!