Customizable watch strap including straps, buckle, latch, and retainer loops to fully replace any part of a standard watch strap (except the metal spring bars that anchor it to the watch). 

The following characteristics can be customized:

• Strap length, width, and thickness
• Hole diameter for spring bars and latch bar (can be different)
• Size, number, and spacing of strap holes
• Thickness of buckle
• Width and length of latch (and associated cutouts)
• 3 different buckle styles (the default Medium one is usually best)
• Optional border and/or extruded SVG pattern printed onto the strap faces (pattern requires using the OpenSCAD desktop application; example SVG included)

Additional Features:

• Customizable cutouts in strap loops to accommodate spring bars with quick release pegs
• A piece of filament can be used as the bar that connects the buckle to the latch and strap 

I've used this to replace broken straps for two different watches and they've both held up very well for years of daily use. 

They probably aren't as sanitary as commercial rubber/plastic straps due to the tiny grooves that FDM printers produce in the bottom layer, but dish soap and vigorous scrubbing with a toothbrush does a decent job at cleaning them. 

Straps and loops should be printed in a flexible filament like TPU, and on a smooth bed for maximum comfort. The buckle is best printed “nose-down” so the arms are vertical, as shown in the picture below. There's not a lot of build plate contact, but it's small enough that it seems to work fine when printed on a textured plate. This orientation provides the best combination of strength and comfort.