The Knots" rubber medic bracelets are super simple and LATEX FREE! They come in one size fits most. Size is determined by where you place the knot. We like to use a square knot which gives the bracelet a more finished look and is ultra secure. Simply ask someone to tie the knot while on your wrist or you may tie it yourself. Pull the knot tight and slip the bracelet on. Once the bracelet is on and you are comfortable with the knots tightness you may cut the ends or leave them. This medic bracelet will be your custom fit! The universal medical ID bracelet is sold with the Contempo ID. CLICK HERE Bracelets Sold Separately TO ORDER MORE ATTACHABLE BRACELETS TO GO WITH YOUR COLLECTION.