Made of material with long life, more durable, for rigidity and durability, specially treated We provide different springs with different pressures to meet your different needs.which is sufficient for most scenarios. suitable for a wide range of applications.A good replacement for the broken one. Strong and not easy to break, long service life, and can provide stable performance. Suitable for equipment, snacks, tricycle doors, advertising bars, soft boxes, flap windows, hoods, equipment flap lids, sticker car flap doors, advertising bars, light boxes, sash windows and hood.