There are several types of stainless steel hexagonal bolts, each with its own specific properties and uses. Here are a few common ones:

1. 18-8 Stainless Steel Bolts: Also known as grade 304 stainless steel, these bolts are corrosion-resistant and suitable for general-purpose applications. They offer good strength and excellent resistance to oxidation and most chemicals.

2. 316 Stainless Steel Bolts: Grade 316 stainless steel bolts are highly corrosion-resistant and commonly used in marine environments or applications exposed to saltwater or harsh chemicals. They provide superior resistance to pitting and crevice corrosion.

3. 410 Stainless Steel Bolts: These bolts are made from a martensitic stainless steel that offers good strength and moderate corrosion resistance. They are often used in applications where high strength and moderate corrosion resistance are required.

4. A2 Stainless Steel Bolts: This is a common designation for metric stainless steel bolts, similar to 18-8 stainless steel. A2 stainless steel bolts are widely used in Europe and have similar properties to 304 stainless steel.

5. A4 Stainless Steel Bolts: Another metric stainless steel designation, A4 stainless steel bolts are similar to 316 stainless steel and offer excellent corrosion resistance. They are commonly used in marine and coastal applications.