Especially useful in metal-to-metal or where heavy duty fastening is required. A machine screw, also called a stove bolt, is generally a smaller fastener threaded the entire length of its shank..50 x 25 mm Phillips Flat Machine Screw, Plain Stainless Steel, 20 PK Machine screws are used in fastening nearly all types of hard materials.
.1/4"-20 x 1" Zinc Plated Grade 5 Steel Coarse Thread Carriage Bolts 100PK A carriage bolt has a domed or countersunk head, and the shank is topped by a short square section under the head.