Be a Revolution: How Everyday People Are Fighting Oppression and Changing the World―and How You Can, Too

Mathematical Quickies: 270 Stimulating Problems with Solutions (Dover Recreational Math)

SPI Round Bar Center Finder, 0.2" Head Diameter, 3/8" Shank Diameter, Mechanical, Cylindrical Contact, Part #13-150-8

SPI Rectangle Steel Gage Block, 4 Inch, Grade AS-1, NIST Certified

SPI Steel Gage Block, Rectangle, 0.75 Inch, Grade AS-1, NIST Certified

SPI Rectangle Steel Gage Block, 2 Inch, Grade AS-1, NIST Certified, Dimensional Measurement Tool

SPI Rectangle Steel Gage Block, 0.05 Inch, Grade 0, NIST Certified

SPI Adjustable Parallel, 3/8 to 1/2 Inch Range, 1-3/4 Inch Long, 9/32 Inch Thick, Part #14-872-6

SPI Steel Parallel, 6" Long x 1" High x 1/2" Thick, 0.0003" & 0.002" Parallelism, Matched Pair