Vacuum Tube - 6AB7 / 1853, Pentode, Remote Cut-Off, RF
New-Old-Stock (NOS) tube.
Also known by US military identifier VT-176.
The 6AB7 / 1853 is a high transconductance semi-remote cut-off amplifier tube. This tube is designed for television RF and IF amplifier service. Precautions should be taken not to exceed dissipation rating with expected line-voltage fluctuations, especially with fixed-bias operation.