For SLE 12 SP5 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/systemsmanagement:Uyuni:Retail/SLE_12_SP5/systemsmanagement:Uyuni:Retail.repo
zypper refresh
zypper install POS_Image-Graphical6
For SLE 12 SP4 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/systemsmanagement:Uyuni:Retail/SLE_12_SP4/systemsmanagement:Uyuni:Retail.repo
zypper refresh
zypper install POS_Image-Graphical6
For SLE 12 SP3 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/systemsmanagement:Uyuni:Retail/SLE_12_SP3/systemsmanagement:Uyuni:Retail.repo
zypper refresh
zypper install POS_Image-Graphical6