Probably started out as a 295-A (sidetone). Converted to a 495-type (anti-sidetone). T is probably for a cold cathode tube used for 4-party selective ringing.* Tube appears to have been replaced with a capacitor. (No ringing capacitor is used when tube is present.)
Definitely a "conversion" done at the WE repair Shop. Cow bells won't fit in a 684-type subset (Bakelite or plastic cover).
*Bell used this method of "superimposed ringing" on many multi-party lines, rather than the frequency selective ringers we all hate to find in Automatic Electric, Kellogg, Stromberg-Carlson and North phones.