Identify 16A or 10A device

I recently ordered 16A switch for controlling Heater.

There is no marking on the device whether 16A or 10A. how do I make sure what I got is a 16A device? by the looks relay seems too small for a 16A device.

the place where I suspect to be relay is shorter than the adjoining connector block, measuring about 13mm

This is 16A . Shorter and broader relay is 16A