Investor PresentationInvestor PresentationUpdate 17 August 2006

Sino-Thai Engineering & ConstructionSino-Thai Engineering & Construction

Public Company LimitedPublic Company Limited

2

Q2-06 P/L Statement

Increase in commodities price and delay in Airport Rail Link pressured overall performance

Consolidated Q2-05 Q2-06 % Change

Construction and service income 3,542 3,574 1%

Total revenues 3,564 3,606 1%

Cost of construction and service 3,333 4,449 33%

Provision for loss of construction projects 4 905

Gross profit 209 (875) -518%

SG&A 83 81 -2%

Interest expense 17 24 41%

Net profit 122 (1,857) -1617%

EPS (Bt.) 0.12 (1.57)

EPS-fully diluted (Bt.) 0.09 (1.38)

Gross profit margin 5.9% -24.5%

Net profit margin 3.4% -51.5%

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Q2-06 Balance Sheet

Consolidated Q2-05 Q2-06 % Change

Cash and current investment 1,732 1,591 -8%

Current assets 7,949 10,767 35%

Total assets 11,877 15,589 31%

Financial debts 1,937 2,066 7%

Accounts Payable 2,701 2,485 -8%

Advance receipt from construction contracts 2,939 4,752 62%

Current liabilities 7,440 10,539 42%

Total liabilities 7,993 11,683 46%

Equity 3,884 3,906 1%

Book value / share (Bt.) 3.82 3.30

Book value / share - fully diluted 2.88 2.89

Gross gearing ratio 0.50 0.53

Debt to Equity ratio 2.06 2.99

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THBmRemaining contract value (as of Dec.05) 28,581 Value of contract signed Y-T-D 10,200 Total 38,781 Deduct Value of contract realized in 6M-06 (6,565)Remaining order book 32,216

Backlog at year end

11,480

28,58126,507

5,813

-10,00020,00030,00040,000

2002 2003 2004 2005

Backlog at year end

Backlog Orders

Note : Company only Update as of 17 Aug. 06

THBm

ORDER BOOK

Newly-Signed Contracts (2006) (THBm)• RPCL Gas Pipeline, RATCH 506• Drainage&Pumping System-SBIA, RID 2,656• Build.A, Gov. Center, Dhanarak 3,173• Car Park B and Convention Hall, Dhanarak 1,738• Utilities, Gov. Center, Dhanarak 1,028• SBIA-Chonburi Lot5, DoH 525

Active Major Projects (THBm)• SBIA Rail Link & City Air Terminal, SRT 12,260• Ratchaburi Power Plant (2x700 MW) 4,341• Kaeng Khoi 2 (1,520MW), Gulf 2,544• South Bkk. Power Plant, EGAT 2,300• BMA Building Phase3, BMA 2,271• Songkla Power Plant, Marubeni 1,760• Administrative Court, Dhanarak Dev. 1,694• Pak Kret Bridge, DORR 1,572•The Park at Chidlom, Hemaraj 1,341

To be signed contracts (THBm)•South Interchange of SBIA, ETA 1,983•ATC-2, Build. Complex, SKEC&GS 502•TOP CDU-3 Revamp, Civil, ABB Process 133

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Infrastructure45%

Energy25%

Building27%

Industrial1%

Environment2%

Government21%

Private21%

State Ent.58%

Infrastructure41%

Industrial6%Environment

0%

Building40%

Energy13%

Private30%

State Ent.40%

Government30%

Backlog

Note: Backlog as at July 2006

Revenue and Backlog Structure

Revenue Breakdown by Client Revenue Breakdown by Type of Work

2005 2005

Note: Actual revenues in 2005 Note: Actual revenues in 2005

Note: Backlog as at July 2006

Backlog

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Sino-Thai Engineering & ConstructionSino-Thai Engineering & Construction

Public Company LimitedPublic Company Limited