M5 M10 Stainless Steel Metal Thumb Screw SUS304 SUS316 Spade head Knurled thumb screw Custom size

Hand screws (sometimes written thumbscrews) are multi-purpose fasteners designed to be tightened and loosened manually without the need for tools such as screwdrivers or wrenches for installation. They have a wide range of useful applications, especially in parts, materials and structures that do not easily support the use of hand or power tools. This is often due to space constraints.

Hand screws and thumb bolts may also be useful solutions in situations where you may need to remove components or panels on a regular basis. They can make tasks such as maintenance or cleaning quicker and easier than using mechanical screws, bolts or rivets that are fully tightened with a driver.

Various types of fasteners and fixings may fall under the broad definition of hand screws. True hand screws or bolts can be distinguished from standard bolts or rivets by their large heads, which provide an easier grip. They have knurled edges around the head to further improve friction and grip when turned by hand. They may have a screwdriver slot in the head if desired. Washers are usually not required to use this type of fastener.

Knurled hand screws are often chosen because they give the user a better grip during manual installation.

These types of knurled bolts and screws are called knurled because of the knurling pattern found around the head of the screw - a series of ridges or bumps formed by machining. Knurling is a widespread manufacturing technique used to improve grip or torque forces between various components and fasteners that are manually installed.

Knurled head hand screws are one of the common applications of this technique and can be found on many stainless steel or nylon nuts, screws and bolts. The pattern of bumps, ridges, or grooves allows for better finger friction against otherwise smooth edges when tightening hand screws.

1. Basic knowledge of stainless steel: Stainless steel is an alloy material with corrosion resistance, and its main components are an alloy of elements such as iron, chromium and nickel. These elements can effectively resist oxidation and corrosion, so that stainless steel has a high degree of durability and aesthetics.
2. Stainless steel maintenance methods:
   • Cleaning: Keeping stainless steel products clean is an important part of their maintenance. You can use mild detergents and soft cloth for cleaning, avoid the use of detergents containing acidic and alkaline components, so as not to damage the surface of stainless steel. When removing dirt, you should try to avoid using irritating cleaning tools to avoid scratching the stainless steel surface. After cleaning, rinse with water and dry with a clean soft cloth.
   • Use of stain remover: For some stubborn dirt, you can use special stainless steel stain remover for cleaning. But before using it, you should carefully read and follow the instructions in the product manual. In addition, stainless steel products on the dirt can be cleaned with alcohol or vinegar, these common cleaners on stainless steel has a certain decontamination effect.

201, 304, 316 are austenitic stainless steel, according to the performance of the non-magnetic, some of the performance of the weak magnetic because of the smelting of the composition of the segregation or improper heat treatment leads to the austenite in a small amount of martensite or ferrite. Austenitic stainless steel corrosion resistance comes from the formation of chromium oxide protective layer on the metal surface.

304 stainless steel is a general-purpose stainless steel that is widely used to make equipment and machine parts that require good all-round performance (corrosion resistance and formability). In order to maintain the corrosion resistance inherent in stainless steel, the steel must contain more than 18% chromium, more than 8% nickel content. 304 stainless steel is a grade of stainless steel produced according to the American ASTM standard.

A2 stainless steel and A4 stainless steel, A2 is a class of 304 stainless steel, A4 is a class of 316 stainless steel, the main difference between the two is here, some of the fastener industry will be 302HQ and 304 referred to as: A2, 316 and 316L (C content of carbon C is less than 03% of the stainless steel, you can increase the 'L' logo) called A4.