What are your hours of operation?

We are open M-F from 8:00AM-4:30PM CST.

How do I request a quote?

Click on the “Request for Quote” link at the top of the page.

How do I place an order?

You can place an order directly through the website or contact one our sales representatives at 1-888-660-0334. PLEASE NOTE: phone orders will be charged freight whereas ordering from the website includes FREE shipping.

Can I order one piece if needed?

For some items, yes you can order one piece. However, on most of our items, we do have minimum order quantities (MOQ’s) on our orders. You can find the MOQ’s either on our website, or by speaking with one of our sales representatives.

How do I know if an item is in stock?

Under "price per piece," you will see "availability." That is where you can see how soon an item will ship. If you need the item faster, please contact us to discuss alternative shipping options.

Why is the price shown on your website sometimes different from the price shown in Google Shopping?

Google shopping shows the price per piece for our highest quantity discount. Please increase your order quantity to get that price (see quantity discounts on the product page for quantity-based pricing)

How do I cancel an order?

If you need to cancel please contact us immediately at 888-660-0334. You may cancel the order until the order has been released to the warehouse for picking. Cancellation is not guranteed.

What payment methods do you accept?

We accept all major credit cards and PayPal for all sales transactions.

I want to apply for credit terms. What is the process needed in order to do that?

Contact our sales team by phone or email and we can send you a credit application. Once approved, we do expect our credit customers to spend a minimum of $10,000 per calendar year.

What is your warranty policy?

ASMC LLC warrants the goods to be free from defects in workmanship and material in the event any of these goods prove to be defective in workmanship or material within a period of six (6) months from purchase. Please see Terms and Conditions for full Warranty Statement.

When and how will my order ship?

The lead time (Availability) is shown on each product page, under the price, as well as on the checkout screen. We are committed to shipping every order within the stated lead time, and often ship earlier. We process orders with expedited shipping as soon as possible, usually the same day, for orders placed before 2PM CDT. Emergency service may be available for some items. Please call. Unless agreed to otherwise in advance, orders will ship complete. Typical backorder times are only a few days, and we will notify you of any backorders. We reserve the right to cancel any order or any part of any order at our discretion. Orders placed on the website with standard shipping ship free to addresses in the continental US. The shipping method for standard shipping orders is determined by our shipping system at time of shipment and is not known in advance. You also have the option of upgrading to UPS ground or a variety of expedited UPS services at checkout for an additional fee.

Can you ship on my UPS account?

Yes. Please select Will Call Pickup as the shipping method, and add shipping instructions to the order comments, including your UPS account number.

Why is part I received different from the part number I ordered even though the part looks right?

We reserve the right to substitute ordered parts for functionally identical parts with different part numbers when needed.

I need exactly 100 pieces for my project. Is it safe to order exactly that amount, or should I get some extras?

All orders are scale counted. While we strive to ship the exact quantity ordered, shipped quantities on small parts can vary +/- 5%. If you want to stay on the safe side, order a few extra pieces.

Do you ship internationally?

Yes. We ship worldwide. We are responsible for international shipments until they leave the United States. After the shipment leaves the United States, it becomes the customer's responsibility.

Do You Offer Any Coupons?

Yes, we run limited time promotions with coupon codes in our monthly newsletters. Please subscribe to our newsletter to find the most up-to-date coupon.

What is your return policy?

Items may be returned within 30 days. Unless the return is the result of our error, the customer pays for return shipping, and a restocking fee may apply. Please see Terms and Conditions for full return policy details.

What is your privacy policy?

Any information collected during your visit is for our use only, and will never be shared with third parties.

Do you charge sales tax?

We collect sales tax of 8.5% on all orders shipped to the state of Illinois. Order shipping outside of Illinois will not be charged sales tax. If you are an Illinois tax-exempt entity, please create a customer account on the website, and contact us to set your account as tax-exempt. Please do not pay tax and then submit your paperwork after the fact. We are unable to refund tax--we can only cancel your order, as long as is not being worked on in our warehouse. You may contact your state tax authority for reimbursement.

Where can I find more information about your terms and conditions?

Please click here for full Terms and Conditions, including our full Return Policy and Warranty Statement.

Are Certs available for your products?

MTRs (Material Test Reports) are available on most items for a $25 per item fee (The fee will be waived for order lines with a value of $50 or more. Exclusions apply). ASMC's C of C (Certificate of Conformance) is available for all items for a $25 per item fee (The fee will be waived for order lines with a value of $50 or more. Exclusions apply). MTRs and/or C of C must be requested prior to or at time of order.

PICTURES ARE REPRESENTATIVE OF ITEM, BUT ARE NOT OF THE ACTUAL ITEM. Product dimensions, finish, head markings, thread length, stamping shape or forging shape, etc., may differ from picture. Products are guaranteed to meet the specifications to which they are manufactured. Specifications allow for tolerances in dimension and shape, which can vary from lot to lot.

5/16"-18 x 6" A307 Grade A Square Head Machine Bolt Low Carbon Steel Hot Dip Galvanized

Price Per Piece: $0.9645

Part #:: 0000-121287
Minimum Purchase:: 300 pieces

PRODUCT SPECIFICATIONS (Part # 0000-121287)
Fastener Type:	Square Head Machine Bolt
Size Description:	5/16"-18 x 6"
Diameter/Nominal Size:	5/16"
Length:	6"
Wrench Size/Across Flats:	0.484-0.500"
Width Across Corners:	0.665-0.707"
Head Height:	0.186-0.220"
Thread Pitch:	18
Thread Direction:	Right
System of Measurement:	Inch
Grade:	A (2)
Material:	Low Carbon Steel
Finish:	Hot Dip Galvanized
Head Type:	Square
Drive Type:	External Square
Standards Met:	A307
Average Piece Weight:	0.1328000 lbs.

Square head bolts, or square head machine bolts offer a large bearing area for positive gripping; primarily used nowadays for aesthetic projects that create a rustic look or to match existing fasteners; comes in both fully threaded and partially threaded pitches. Square head bolts are sometimes selected over hex heads because the head will fit neatly in a channel.

Product Reviews

Write a Review

5/16"-18 x 6" A307 Grade A Square Head Machine Bolt Low Carbon Steel Hot Dip Galvanized

Price Per Piece:

Total Quantity:

Total Price:

Product Reviews

Recommended Products

5/16"-18 x 5" A307 Grade A Square Head Machine Bolt Low Carbon Steel Hot Dip Galvanized

5/16"-18 x 1" A307 Grade A Square Head Machine Bolt Low Carbon Steel Hot Dip Galvanized

5/16"-18 x 4" A307 Grade A Square Head Machine Bolt Low Carbon Steel Hot Dip Galvanized

5/16"-18 x 2" A307 Grade A Square Head Machine Bolt Low Carbon Steel Hot Dip Galvanized

5/16"-18 x 3" A307 Grade A Square Head Machine Bolt Low Carbon Steel Hot Dip Galvanized