How to create form with border like the tray menu or volume control

I have a borderless form. How do I give it a border like that of the volume control or tray menu, like below?

Attachment 128087

Thanks.

Set the following form's properties
ControlBox = False
MaximizeBox = False
MinimizeBox = False
Text = ""

To add to 4x2y's comment, that's not a borderless form... It's fixed3d

Thank you! Also, I didn't know what else to call it, I guess technically it does have a border haha.