This is a new custom made brown case/cover for vintage HP Woodstock and HP Nut series calculators. It is felt lined with a pocket inside.
Dimensions in inches (W = Width, L = Length, D = Thickness)
4.25" W x 6.5" L x 1.25" Deep
Belt loop: 1.5" W
It fits these vintage calculators as well as the smaller current models many others:
HP 21, 25, 25c, 29c, 22, 27, 41c, 41cv, 41cx
HP 10b, 10bii, 10bii+, 11c, 12c, 12c platinum, 15c, 16c, 20b, 20s, 32s, 32sii
Manufactured by reliable HP Calculator Dealer since 1993 Samson Cables.