--- Pre-wound embroidery bobbin thread. . ---Used for computer embroidery & sewing below thread, these are an excellent value for embroiderers looking to save time. it realized to consistent draw-off tension from beginning to end through reduces friction, static charge. It means less downtime and protect the thread from breaking on today's high speed equipments. .. . . ---Size / Length: L-size: Cardboard sided or Sideless with core(125m). Plastic Sided with core(100m) A-size: Plastic sided with core(105m). M-size: Sideless with core(230m). --- Material : Polyester filament 70D/2 - High tenacity yarn. Polyester Filament 75D/2 - Mid tenacity yarn. Nylon filament 210D/2, 210D/3, 420D/1, 630D/1 Spun Polyester 60s/2 --- Packing: 144pcs /white box, 40box/carton.