Select you systems architecture, supported are i386 (32bit) and amd64 (64bit).
OPNsense can be downloaded from a large range of mirrors located in different countries, you may want to select the fastest options for your location.
Checksum files next to the images may not prove authenticity of images
on any particular mirror. The checksums can also be found in the forum
annoucements, mailing lists, blog posts or GitHub. Please double-check.