With no shoulder, these nuts can be bottomed out in a hole, or set below a surface. The tapered interrupted thread design ensures positive locking and good pull-out resistance.
Can also be used for curved work, or when you want to set the nut deep to accommodate over-long bolts.
Insert nuts are die-cast from a zinc alloy, and require a 6mm hex key. As with any fastener, pre-drill size will vary from 8.7mm to 9.1mm, depending on the material thickness and density.