Dust Hose Adapter
Lets you easily and securely hook up a 4'' hose directly to tools with a standard 2-1/4'' port. Works with most benchtop tools. Technical Details:Small end is 2-1/4'' OD, 2'' ID. Large end is 3-7/8''OD, 3-11/16'' ID. Overall length is 3-1/4''(Large end is 1-5/8'' long, small end is 1-1/2'' Long, 1/8'' separating ridge.)