Micro chucks and collet adapters allow the use of smaller shank accessories without changing the handpiece collet. Ideal for use with very thin shank drills. See chart for Gauge – Inch – Metric equivalents. A-M50 – 2-1/4″ length – from 3/32″ to drills #70-80 A-M53 – 2-1/16″ length – from 3/32″ to 3mm rods A-MC2 – 1-5/16″ length – from 1/8″ to drills #60-80 A-M52 – 1-5/16″ length – from 3/32″ to 1/16″ friction grip burs A-M50, A-M53, A-MC2 & 10,000 RPM Max Speed. A-M52 20,000 RPM Max Speed. Micro Chucks and Collet AdaptersNickel-plated Micro Chucks A-M50 and A-MC2 hold various sizes of drills and have a 1/4″ head diameter. A-M53 also has a 1/4″ head diameter & holds 3mm rod accessories. Collet Adapter A-M52 (3/16″ head diameter) is used to “step down” the collet size without having to actually change the collet in your handpiece. This is a great way to easily use a smaller diameter shank accessory quickly without any of the work involved with changing collets.Check Out The Foredom Tools Catalog SKU: FOR-A-M50 UPC: 098666881507 Brand: Foredom MPN: A-M50 Made In: United States Micro-Tools makes every attempt to provide accurate information for each item. Actual packaging and/or specifications may be slightly different from the information and picture provided.X