IBM 3251/3276/3278/3279/8775 Display Station 75-key Typewriter Keyboard
327X-75 type Model B
eg, P/Ns 4941777, 4941783, 4941807, 4941813, 4941819, 4941825, 4941831, 4941835, 4941847, 4941853, 4941859, 4941871, 4941877
IBM-made 75-key (most) or 76-key (Japan) [data] typewriter keyboard for primarily the IBM 3276 Control Unit Display Station, 3278 Display Station and 3279 Color Display Station, but was also used with the IBM 3251 Display Station and 8775 Display Terminal. This variant doesn't have a numeric lock.
Relations
Derivative designs

IBM 3278 Model 2A Display Console 75-key Operator Control Panel Keyboard (IBM 43X1 w/o channel-to-channel variant)

IBM 3278-2A/3279-2C Display Console 75-key Operator Control Panel Keyboard (IBM 308X w/ SCCP variant)

IBM 3278-2A/3279-2C Display Console 75-key Operator Control Panel Keyboard (IBM 43X1 w/o channel-to-channel and power-on variant)