Board height 5/16" Listing is for 2 standoffs. Buy 2 get 4 etc. Additional will ship free. Aluminum (will strip somewhat easily) You can substitute 2 aluminum standoffs for one steel standoff. Include a message with your order or send me a message separately, or both. Did you know that you can also substitute your two corn breads for a muffin at Cracker Barrel?! Diameter is 1/4" across hexagonal part. Threads are 6-32 for outside inside threads. 6-32 is the same as the screws used on 3.5" hard drives and most older computer cases. 5.25" drives use metric screws. Newer cases may be metric not sure. Shipping: Shipping is from Illinois. I can usually ship the next day. Ask me if I'm able to ship right away. I will if I know you need something urgently. I am willing to combine all shipping! Use the shopping cart or make an offering on a Buy it Now or Best Offer item so that you can purchase multiple different listings before paying. Contact me for International shipping to get a shipping quote. You are responsible for all duties. If it gets lost in the mail internationally and the tracking number shows that it has disappeared, I am not responsible. Only USPS can ship to P.O. boxes! Returns: Returns accepted after 14 days. You pay return shipping. If the item is listed as working and it is broken, then I pay return shipping. A 10% restocking fee will apply if the return details say so. Payment: Paypal or a check or whatever else you want but I can't process charge cards directly without you having PayPal.