1These set screws are made of stainless steel for rust-resistance and long service life. 2They are multipurpose hex socket head set screws that you can simple drive with hex keys. 3There are many common sizes and you can concentrate on your project without worrying about not having the correct screws. 4Get these total 300 pieces screws so you won't be running off to the hardware store for a set screw for quite a while. 5Well packed and assorted in a resealable transparent box for convenient carry and storage.Features: These set screws are made of stainless steel for rust-resistance and long service life.They are multipurpose hex socket head set screws that you can simple drive with hex keys.There are many common sizes and you can concentrate on your project without worrying about not having the correct screws.Get these total 300 pieces screws so you won't be running off to the hardware store for a set screw for quite a while. Well packed and assorted in a resealable transparent box for convenient carry and storage.Specification: Material: Stainless steelTensile Strength: 12.9 grade Size and Quantity: M3*3 40PCS M3*4 40PCS M3*6 40PCS M4*4 30PCS M4*6 30PCS M5*5 30PCS M5*8 30PCS M6*6 20PCS M6*10 20PCS M8*8 20PCS Weight: 166g / 5.9oz (approx.) Package list: 1 box * Screws