what are the .udeb files?

I'm trying to create a local repository, but I do not download the files
.udeb
as podr'ia also download these files?

#!/bin/sh
ARQUITECTURA=i386
METODO=http
RAMA=jessie
HOST=packages.devuan.org
DIR_MIRROR=/mnt/datos/sistemas/linux/devuan/merged
SECCIONES=main,contrib,non-free

echo
"======================================================================"
echo "Actualizando los repositorios DEVUAN 'merged'; main, contrib,
non-free"
echo
"======================================================================"
echo ""
debmirror -a ${ARQUITECTURA} \
-s ${SECCIONES} \
-h ${HOST}/merged \
-d ${RAMA} -r / --progress \
-e
${METODO} --postcleanup --ignore-small-errors --ignore-missing-release --ignore-release-gpg
--nosource --allow-dist-rename \
--diff=none \
${DIR_MIRROR}

Best Regards
========
| ISMAEL |
========