A whole roll of synthetic whalebone for corsetry and costume
This is top notch plastic boning made especially to simulate whalebone. It's a good lightweight alternative to steel, it can be moulded with heat.
Smooth and white, it provides good support for period style corsets (particularly Victorian styles) and as usual, the more you use, the more support you get.
The 6mm with is 1.5mm thick as this is the most popular weight for this width - it therefore suits modern corsetry too.
The 12mm width is also a sturdy 1.5mm thick and can be used for bustles, cages and lightweight paniers.
The 5mm width is 1mm thick and is therefore particularly good for boning stays.
All widths can also be drilled with a dremmel to make a small hole in each end which can then be stitched through to secure bones in channels.
If the boning is curled when it comes off the roll, simply straighten it out with a lukewarm iron.
Use an emery board to smooth the tips - the sort used by nail technicians to file acrylic nails will be the best, it has a low grit number of around 80 grits (as opposed to the fineer nail files which have a 200 grit number - can you tell what I did in a previous life?)