Ultra Clean (UCTT) 8-K Regulation FD Disclosure

Exhibit 99.1

Revenue Growth Drivers o Outsourcing o Other Subassemblies o Geographic Expansion o New Customers

Robust Metrics December 31, 2003 December 31, 2004 DSO (QTR) 34 33 Inventory Turns (QTR) 11.5 8.8 Cap Ex (m) (YTD) $0.7 $3.3 EBITDA (m) (YTD) $3.6 $15.8 ROIC (YTD) 2% 24% See Company website for GAAP reconciliations of EBITDA and ROIC.

UCT's Differentiated Business Model o UCT is a System Integrator - Able to Scale Infrastructure Costs - No Product Risk, Low R & D Expenses and Low Sales / Service Costs (vs. OEM Component Manufacturer) - Low Capital Expenditures (vs. Electronic Manufacturing Services) UCT achieves above average growth in Operating Margins