United Space Alliance technician Larry Tanner places Teflon-coated fabric on either side of the gap filler before installation. The fabric ensures the glue remains in place until bonded and then the fabric is later removed. Discovery is being processed in Orbiter Processing Facility Bay 3 at NASA’s Kennedy Space Center. This work is being performed due to two gap fillers that were protruding from the underside of Discovery on the first Return to Flight mission, STS-114. New installation procedures have been developed to ensure the gap fillers stay in place and do not pose any hazard during the shuttle's re-entry to the atmosphere. Discovery is the scheduled orbiter for the second space shuttle mission in the return-to-flight sequence.