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1.6.6. Additional Services The non-core, hot-deployable services are added to the deploy directory. They can be either XML descriptor files, *-service.xml, *-jboss-beans.xml, MC .beans archive, or JBoss Service Archive (SAR) files. SARs contains an META-INF/jboss-service.xml descriptor and additional resources the service requires (for example, classes, library JAR files or other archives), all packaged up into a single archive. Similarly, a .beans archive contains a META-INF/jboss-beans.xml and additional resources.