Donald M. Townsend

SC Simpson Dura-Vent Company: 1 patents #1 of 2Top 50%

📍 Mill Valley, CA: #2 of 19 inventorsTop 15%

🗺 California: #2,144 of 10,592 inventorsTop 25%

Overall (1989): #118,862 of 140,708Top 85%

Patents 1989

Issued Patents 1989

Showing 1–1 of 1 patents

Patent #	Title	Co-Inventors	Date
4846147	Chimney liner system	John R. Jacklich	1989-07-11