Twin Systems is also listed under the following categories: Standard Yellow Pages Heading (SYPH) Categories:

• Plumbing, Heating, Air-Conditioning

North American Industry Classification System (NAICS) Categories:

• Plumbing, Heating, And Air-Conditioning Contractors > Miscellaneous Services Related To Plumbing, Heating, And Air Conditioning
• Site Preparation Contractors > Plumbing, Heating, Air Conditioning

Standard Industry Classification (SIC) Categories:

• Plumbing, Heating And Air Conditioning > Plumbing Contractors By Name (Except Franchise)
• Plumbing, Heating And Air Conditioning > Miscellaneous Services Related To Plumbing, Heating, And Air Conditioning