Tape & Reel (TR) is the solid enclosure in which optical attenuator is packaged.The RF Attenuator is convenient to ship overseas because it is packed in a 24-VQFN.
HRF-AT4510-TR Features
HRF-AT4510-TR Applications
There are a lot of Honeywell Aerospace HRF-AT4510-TR Attenuators applications.