Unusual bolts securing holden viva thermostat

[Medtech1]

G'day gurus. I'm replacing the thermostat in my 2009 Holden viva and it is secured by 3 unusual looking bolts which I have no tools for (see pics below). Can someone advise what tool is required. The best way to describe them is star shaped posts.

Cheers and TIA.

[Ben C34]

External torx or e-torx

 

 

Often a normal 12 point socket will work anyway

[Duncan]

agreed, a 12 point should get it....what a PITA to put on there.....

[GTSBoy]

Typical Daewoo stupidity.

[joshuaho96]

I'm afraid to strip stuff so I would get the right socket but yeah that's external torx. I've also seen 12 point hex before when I changed a fraying seatbelt out on my car.