M5 Jack Nut, also known as a Spyder Nut because of its spider like design when installed. A versatile insert nut for brittle, thin, or soft, materials. Often used for clamping two pieces of metal together.
The Jack Nut is placed into a pre-drilled hole and when tightened the body of the Jack Nut collapses on the blind side of the material forming four splayed legs.
These collapsed legs on the inside / blind side of the materials surface allow for a secure and reusable threaded insert.
Often used for joining thinner sheets of material together or to install a threaded insert into thin material. These Jack Nuts are also known in the trade as Spyder Jack Nuts or Pop Jack Nuts and used by DIY enthusiasts and professionals alike.