4.2. PACKAGING AFTER FINAL CLEAN4.3. All vacuum parts final cleaned at Veeco or an equivalent facility should be individually packaged in the following sequence to ensure part cleanliness:4.3.1. Put into polyethylene bags or wrap in polyethylene sheets within 30 minutes of cooling.4.3.2. Heat seal closed. Backfill with Argon or Nitrogen. Vacuum heat sealing should not pull material tight to surface of the part especially on Grit Blasted Shield and Thermal Coated Shield parts. Pulling the plastic that tightly could cause the plastic to wear against the rough metal surfaces in the bag and rip holes in the plastic material.4.3.3. Mark part package with part number and latest revision letter.4.3.4. Wrap in bubble-wrap for protection prior to transport.