We have single fittings like this on all our windows.
https://www.bunnings.co.nz/yale-slimline-window-handle-face-fixed-right-hand_p00276053
They have a little attached wedge/packer which is made of plastic/rubber, that drops down when the window latch is being "closed" which means the window closes snugly.
As part of our attempt to provide some additional ventilation in our rooms, we are intending to switch to something similar to these:
https://www.bunnings.co.nz/yale-black-fix-right-hand-styleline-window-catch_p00383909
The problem being that these don't have the same wedge/packer. I can see some are sold seperately, however as best I can see, this involves "attaching" them to the base of the window, and requires holes to be drilled to accomodate it. I am not really super excited about drilling 4 holes in each window and wondering if anyone had any experience or suggestions on a good alternative?