Bausch and Lomb 3.5X Magnifying Lens
3.5" (88mm) Long
1.435" Diameter at the bottom (There's a lens retaining ring 0.25" wide)
Barrel is 2.9" in length and measures 1.372" dia.
The hexagonal cover measures 0.132" thick and is 1.5" side-to-side across the flat surfaces (see photos)
Has written on the side of the barrel:
"Bausch & Lomb
Opt. Co.
Rochester, NY
USA
3.5X"
Listed with ExportYourStore.com