6" Proportional Scale also referred to as 6- Inch Proportion Wheel

Easily determine new proportional sizes.  Also easily determine percentage of enlargement or reduction for such uses as photocopy machines.

6-inch outer circle scale with 5-inch inner circle scale.  Outer scale marks on 6-inch outer scale circle are for Reproduction Size.  Outer scale marks on 5-inch circle scale are Size of Original.  Inside circle scale also provides Percentage of Original Size and Number of Times of Reduction.

Has larger numbers and larger circles to rotate for ease of manipulation as compared to  5-Inch Proportion Scale CTHRU-PS69.

Made in USA from C-Thru Ruler Company.