This design is a EB letter shape bookband, which is available in all letters of the alphabet, in all the different patterns.
They are slightly padded (a little less than the hanging decorations, so's not too be too bulky inside your book) with a colour co-ordinated elastic band approx 6mm wide & 34cm long, to hopefully accommodate a range of book sizes & thicknesses!
 
The letters measure approx 9cm high, and the width depends on the letter chosen, for example the letter M shown is 10cm wide, the letter B - 7.5cm wide. 
These bookmarks are made with genuine Emma Bridgewater prints, and are made up of 2 layers of fine padded felt.
 
Simply choose your letter and pattern.
All my decorations are handmade to order in my Sussex studio.