From Ged Dodd, "A Russian State Customs Tax seal submitted by Stuart F Elton and found at Rotherhithe on the Thames Foreshore by Judith Hazell. The obverse has the Lesser Arms of the Russian State in operation from 1883 -1917.
The reverse has *ДН*ИВСКОИ.Т. around the number 30.
*DH* IVSKOI . T where T = TAMOЖHЯ = Customs Tax.
I think the rest "says" ..pertaining to the Inspector Number 30.
.... .see ref IDS 1089 on The PeaceHavens Project - Seal Numbers 1001 - 1100
Further relevent information can be found on The PeaceHavens Project - Russian State Arms Custom Tax Seals."