1/4"-20 Furniture Screws Threaded Inserts set:80 pieces 1/4"-20 Furniture Screws Comes with 9.0mm White steel twist drill and 6mm Hex Spanner.Features of insert nut:These threaded inserts are inserted into a pre-drilled hole by screwing in, in that case the external protrusions bite into the wood, preventing the nut from either turning or pulling out.Suitable application:Easy to install and with good stability, have a good effect in the furniture combination, suit for all Furniture woods of pine, plywood, fiberboard, etc..How to use: pre-drill/ drill a suitably sized hole and enter with an Allen tool screw.PS:1. The hole depth is 1-2mm longer than furniture screw;2. If that hardness of the wood material is high, enlarged a little bit the screw hole to fit the screw.Specification:Material: high hardness and high quality carbon steelSize:Thread Type: 1/4"-20External Diameter:0.410”(10.5mm)Inside Diameter: 0.315”(8mm)Total Length: 20mm.Drill: 9.0mmHex Spanner: 6mmQuantity:80 x Furniture Screws1 x Drill1 x Hex SpannerNote: Small objects and sharp drill bits, please keep away from children