Intimation under Regulation 30 of the SEBI (Listing Obligations & Disclosure Requirements) Regulations, 2015-Resignation of Director

HINDUSTHAN INSULATORS & INDUSTRIES LIMITED THE HINDUSTHAN GROUP® (Formerly known as HINDUSTHAN URBAN INFRASTRUCTURE LIMITED) September 30, 2026 The Listing Department, BSE Limited, Phiroze Jeejeebhoy Towers Dalal Street, Mumbai- 400001 Scrip Code: 539984 Sub: Intimation under Regulation 30 of the SEBI (Listing Obligations and Disclosure Requirements) Regulations, 2015-Resignation of Director Dear Sir/Madam, In compliance with Regulation 30 of SEBI read with Schedule-III, Part-A, Para-A of SEBI (Listing Obligations and Disclosure Requirements) Regulations, 2015, (‘Listing Regulations’) as amended and SEBI Master Circular dated January 30, 2026, we wish to inform you that Mr. Shyam Sunder Bhuwania, Non-Executive, Non-Independent Director of the Company has given a notice of resignation from the said position with effect from September 29, 2026 due to his advanced age. The details as required under Regulation 30 read with Schedule III – Para A(7C) of Part A of the Listing Regulations and SEBI Master Circular No. HO/49/14/14(7)2025-CFD- POD2/I/3762/2026 dated January 30, 2026, are enclosed as ‘Annexure-A’. A copy of the email dated September 29, 2026 intimating the resignation is enclosed herewith as ‘Annexure-B’. This is for your kind information and records. Thanking You, Yours Faithfully, For Hindusthan Insulators & Industries Limited (Neha Kejriwal) Company Secretary & Compliance Officer M.No. F12381 Regd. Office: Kanchenjunga (7th Floor) 18, Barakhamba Road, New Delhi-110 001 CIN: L31300DL1959PLC003141 Contact: +91-11-23310001, 02, 04 & 05 I Email: hiil@hindusthan.co.in, investors@hindusthan.co.in I Website: www.hindusthaninsulators.com Insulators & Electricals Company: Faridabad Warehouse: Guwahati Warehouse: Gwalior: Bangalore: 1-8, New Industrial Area, 12/1 Milestone, Plot No. lC, Brahamaputra Industrial Area, Sy. No. 194, 195/1 & 196/1, P.B. No. 1, Mandideep-462 045 Delhi Mathura Road, Industrial Park, P.O. Birla Nagar, Kannamangala Village, Bidarahalli (M.P.) Faridabad -121 003 Viii.: Silla, P.O. College Nagar, Gwalior -474 004 Hobli,Bangalore East Taluk, hiil.iec@hindusthan.co.in (Haryana) North Guwahati, (M.P.) Bangalore - 560 115 (Karnataka) hiil.fbdwh@hindusthan.co.in Distt. Kamrup -781 031 (Assam) hiil.gwl@hindusthan.co.in hiil.blr@hindusthan.co.in hiil.gwtwh@hindusthan.co.in HINDUSTHAN INSULATORS & INDUSTRIES LIMITED THE HINDUSTHAN GROUP® (Formerly known as HINDUSTHAN URBAN INFRASTRUCTURE LIMITED) ANNEXURE-A Disclosure of information pursuant to the SEBI Master Circular HO/49/14/14(7)2025- CFD-POD2/I/3762/2026 dated January 30, 2026 Resignation of Mr. Shyam Sunder Bhuwania as Non-Executive, Non-Independent Director S.N. Particulars Details 1. Reason for change viz. appointment, re Resignation of Mr. Shyam Sunder -appointment, resignation, removal, death Bhuwania as Non-Executive, Non- or otherwise; Independent Director of the Company due to his advanced age (82 years) with effect from September 29, 2026 2. Date of appointment/re- September 29, 2026 appointment/cessation (as applicable) & term of appointment/re-appointment; 3. Brief profile (in case of appointment) Not Applicable 4. Disclosure of relationships between Not Applicable Directors (Applicable in case of appointment of a Director) Regd. Office: Kanchenjunga (7th Floor) 18, Barakhamba Road, New Delhi-110 001 CIN: L31300DL1959PLC003141 Contact: +91-11-23310001, 02, 04 & OS I Email: hiil@hindusthan.co.in, investors@hindusthan.co.in I Website: www.hindusthaninsulators.com Insulators & Electricals Company: Faridabad Warehouse: Guwahati Warehouse: Gwalior: Bangalore: 1-8, New Industrial Area, 12/1 Milestone, Plot No. lC, Brahamaputra Industrial Area, Sy. No. 194, 195/1 & 196/1, P.B. No. 1, Mandideep-462 045 Delhi Mathura Road, Industrial Park, P.O. Birla Nagar, Kannamangala Village, Bidarahalli (M.P.) Faridabad -121 003 Viii.: Silla, P.O. College Nagar, Gwalior -474 004 Hobli,Bangalore East Taluk, hiil.iec@hindusthan.co.in (Haryana) North Guwahati, (M.P.) Bangalore - 560 115 (Karnataka) hiil.fbdwh@hindusthan.co.in Distt. Kamrup -781 031 (Assam) hiil.gwl@hindusthan.co.in hiil.blr@hindusthan.co.in hiil.gwtwh@hindusthan.co.in ANNEXURE-B From: Shyam Sunder Bhuwania <ssbhuwania@gmail.com> Date: 29 September 2026 at 11:39:30 AM IST To: raghav.mody@hindusthan.co.in The Chairman, Hindusthan insulators & industries limited Dear Sir, I hereby resign from the membership of the Board with immediate effect .This is because of my advanced age. I am thankful to all for the cooperation during my 60 years of association . I shall always be available for any work required of me. With best regards , Shyam Sunder Bhuwania