The Tool Holder Is Made In The Usa By Icarbide And Measures 3/8" X 3.5". For all CAT40 Spindle Tool Holder, High precision, cost-effective, USA quality. Advantages of shrink tool holders: 1. Fast loading and unloading of tools, using heat shrinking machine to heat, 13KW high power can complete the tool installation and clamp within 5 seconds, cooling only 30 seconds, the unique water cooling device can prevent the accuracy of the tool holder from deteriorating. 2. High precision and small runout. The tool installation part does not have components such as nuts and collets required by collet chucks, simple and effective, cold shrinkage clamping is strong and stable, tool deflection ?3?, reducing tool wear and ensuring high precision during high-speed machining. 3. The crown is small and widely used. The ultra-thin tip part and abundant tool holder shape changes can be widely used in high-speed, high-precision machining and deep hole machining. 4. Simple and efficient, long life. Hot loading and unloading operation, even if the same tool holder is hot loading and unloading more than 2000 times, there will be no change in accuracy, stable performance, and long service life. The weakness of shrink tool holders: 1. Need to buy a heat shrink machine, thousands to tens of thousands are available. 2. After thousands of times of use, when the oxide layer is peeled off, the accuracy is not so high. Product Features Balanced to G2.5 25000rpm High Precision: TIR 2?m or 0.0001" Bore Diameter: 3/8 " Gage length: 3.5" For All CAT40 Spindles Shipping: Shipping is complimentary within the lower 48 US States. We Do Not Ship to PO/APO Boxes, HI or Alaska We Do Not Ship Outside of the Continental US All items ship within 24-72 hours of Payment For large items that require Freight shipping a valid phone number is required to call and schedule your delivery Terms of Sale and Feedback: Feedback is extremely important to us and If you are satisfied with our transaction, please take a moment to leave Positive Feedback. YOUR Satisfaction is our #1 Priority! If there are any issues, PLEASE contact us BEFORE leaving a neutral or negative rating so that we may resolve any concerns. We PROMISE we can make you happy if you give us a fair chance. Returns / Concerns: All items qualify for returns within 14 - 30 days of receipt. Buyer is responsible for return shipping on any item that is not damaged Please be sure this is an item you want before making your purchase. Customer Satisfaction is our TOP priority! All items are IN STOCK at time of listing. Inventory changes constantly and it is impossible to maintain a perfectly accurate count of all items. Please do not penalize us if we have to issue you a refund! Thank You For Your Business!