Notice that the late-war smooth-side canteen has had the bottom loop removed; this was done postwar to probably thousands of these that remained on hand unissued as surplus items. They then received dark khaki canvas covers and new leather straps with hooks on either end that engaged new triangular "loops" attached to the remaining two original loops. Then in their new configuration they were issued in the 1890's, particularly for the Spanish-American War. That however doesn't make them any the less genuine Civil War-manufactured items; I took one of these and "retrofitted" it for reenacting purposes in the 1970's by removing the triangles, re-soldering a repro loop at bottom, and covering it with a repro wool cover and white cotton canvas strap!