Check the listing for details. Positive / Reverse Thread chuck of lapidary grinding machine for grinding disc. Condition: New. Listed at 25.99 USD. Positive / Reverse Thread chuck of lapidary grinding machine Positive / Reverse Thread chuck of lapidary grinding machine for diamond grinding disc 1/2" arbor hole, Inner diameter of long tail 3/4 inch (19mm) Item Describe: 1. 100% Brand New and High Quality 2. Type : Positive Thread chuck / Reverse Thread chuck 3. Material: Steel 4. Outer diameter of head: 1/2 inch (12.7mm) 5. Inner diameter of long tail: 3/4 inch (19mm) 6. Total Length: 72mm Feature : Accepts accessory grinding disc with 1/2 inch(12.7mm) arbor hole. Such as: 6 inch diamond grinding disc with 1/2 inch arbor hole; Only suitable for lapidary grinding machine with 3/4 inch (19mm) mounting rod; Two types Thread chuck for different lapidary grinding machines: Positive Thread chuckPositive Thread chuck is suitable for the right-handed grinding machine : When the operator sits in front of the machine, the water basin of the machine is on the right hand side of the operator. It is more convenient to use the right hand to hold the stone for operation. The connecting rod of the machine usually Anticlockwise rotation, the matching chuck is Positive Thread chuck. Reverse Thread chuckReverse Thread chuck is suitable for the left-handed grinding machine: The water basin of the machine is on the left hand side of the operator. It is more convenient to use the left hand to hold the stone for operation. The connecting rod of the machine usually rotates clockwise, the matching chuck is Reverse Thread chuck.New, Unused Blade - Not in Original Packaging These chuck were originally packaged in oil so you will see several oil spots on the surface. Regular Air postage from China to Worldwide and take 15-30 days delivery to your home. We will send out your order within 1-2 days after payment has been received and cleared. Please let us know if you are looking for other accessories or hardware