An enclosure of Tape & Reel (TR) is used to package the optical attenuator.Shipping overseas is convenient due to the RF Attenuator's packing in 1206 (3216 Metric).
E-TA3216 T 2DB N8 Features
E-TA3216 T 2DB N8 Applications
There are a lot of Nidec Copal Electronics E-TA3216 T 2DB N8 Attenuators applications.