Teledyne Hastings DB-20 Reference Tube
3.1 Microns Mercury    DV6M    SN 7749
I do combine items when and if possible or practical.
I Guarantee All My Items To Be As Listed & Described
My Items May Be Picked Up By Arrangement: No Fee
I usually ship immediately upon receipt of payment.
Enjoy your bidding!
LOCxGUNCH