[Amps] Help identifying TCC HV capacitors please

[Peter]

Has anybody any information on old TCC (Telegraph Condenser Co.)  ceramic high voltage capacitors please? 
Two examples from the junk box are  both marked  T.T.C.  "KO 2944/TS".  However one is marked 250pf whilst  the other is marked 120pf. Grey, tubular, approx 28mm diameter and 100mm long. Breakdown voltage?  Suitable for rf coupling? Tempco?  Is the KO number a catalogue range or just an MOD supplier/factory code? 

Thanks!

73       Peter G3YYN