Stretch Magic is a strong plastic elastic; it dosen’t fray like fabric elastics. The 0.5mm diameter is thin enough to thread through tiny beads including delicas. Finish with at least three knots (a dab of glue is also a good idea) or the ends can be crimped, we reccomend tubular crimps as they have smoother edges. We have a range of 25m & 100m reels in 0.5mm and 0.7mm & 1mm diameters in clear & black. We only recommend Stetch Magic to be used in making bracelets. The amount of stretching you need to do to get the stretch magic over your head for necklaces, will over stretch this elastic and it will not return to the original length.