It's a ref CK2008. Not sure of the seconds hand on yours.
Here in a 1938 catalog :
One of mines from around 1937, with wrong winding crown says hello :
And in a 1940 catalog (you will notice that although the same ref, it has a sunken winding crown, like yours, which was not the case in 1937-38 :
One of mines with sunken crown and wrong seconds hand says hello :
Click to expand...