I have purchased many different sized bands; I think the smallest diameter is 3/16 with the widest 1/4. The difference in thicknesses of the actual latex varies greatly among suppliers too.. The thicker ones seem to grasp the hair much tighter, but it is recommended that you cut the band out, the thinner bands and scrunchy type bands come off too easily, to use in the way you suggested because they are really stretchy. I purchased so many, I'm not sure which place has the thicker bands. I know Ladymom sells bands, and perhaps you could PM her and tell her your problem, she may know of a thicker band.
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