November 13, 2020 Subject: The Management Discussion and Analysis for the third quarter ended September 30, 2020 To: President The Stock Exchange of Thailand Well Graded Engineering Public Company Limited

operating results for the 3-month period and 6-month period ending June 30, 2017 To : President The Stock Exchange of Thailand Diamond Building Products Public Company Limited and its Subsidiary (together

Ref. DBP. 111 / 2020 August 10, 2020 Subject : Clarification on Operating Results for the 2nd quarter and 6-month period ending June 30, 2020 To : President The Stock Exchange of Thailand Diamond

); “Thai Stock Exchange” means the Stock Exchange of Thailand; “commercial bank” means any commercial bank under the law governing financial institution business; “depositary agreement” means any agreement

of Thailand considered not appropriated to be executives under the regulations of the Stock Exchange of Thailand: O Yes O No (2) Is under accusation or prosecution under the law governing the

. Information of prohibited characteristics: 2.1 Up to present; (1) Is a person whose name is on the black list or the list of persons whom the Stock Exchange of Thailand considered not appropriated to be

paid up; “Stock Exchange” means the Stock Exchange of Thailand; “related person” means the related person under the Notification of the Capital Market Supervisory Board concerning the Related Party

No. CAZ 002/2019 26 February 2019 Subject: Management Discussion and Analysis Year ended 31 December 2018 Attention: The President The Stock Exchange of Thailand CAZ (Thailand) Public Company Limited

ที่ FPI Ref. FPI.001/2020 25 February 2020 Subject : Management Discussion & Analysis of Performance Results of the year ended 2019 To : Board of Directors and President of The Stock Exchange of

Ref. DBP. 025 / 2018 February 21, 2018 Subject : Clarification on operating results of Year 2017 To : President The Stock Exchange of Thailand Diamond Building Products Public Company Limited and its