These are Joint Connector Bolts (JCB) Stainless Steel 6mm Furniture Bolts. They have a standard M6 thread for compatible stainless JCB barrel connector nuts listed separately at our eBay store as per the link below. They can be installed with a 4mm hex (allen) key as illustrated in the photo section of this eBay listing. 

The different lengths are chosen for the applications with different thickness as shown in the photo.

These bolts can also be used as the standard bolts for other applications.
  • What you get: Please note all lengths of bolts are fully threaded other than  M6 x 30mm are partially thereded as shown in the photo. The photos shown are approximate and to be used as a guide only.
  • Quality: All products are of the high quality and meet the relevant international standards.
  • Stock: We carry a large inventory of stock in Sydney Australia,  so all orders can be sent within next business day of your payment.
  • Postage:  All orders will be posted with Australia Post.
M6 Joint Connector Bolt (JCB) barrel connector nuts as per the link below:

https://www.ebay.com.au/itm/234058428160