Review on 🔽 POWERTEC 70146 Eccentric Reducer: Black, 4-Inch to 2-1/4-Inch by Glenn Cartwright

This adapter is perfect for what it does and where it simply fits (or doesn't fit). The 4" end is a male connector that accepts a 4" dust collection hose. The hose is placed directly on this piece and fastened with a clamp. Now for the little ending, which caused some confusion. If your male hose end is 2 1/8" OD and your tools are 2 1/4" ID, then you know it's a 2 1/8" fitting. Go check it out - then this. For example: I have an enclosed guard that I made for my 12" ShopSmith grinding wheel because it is a major source of hazardous grinding dust. "ID FEMALE Fitting. My store bought vacuum hose is stuck inside. So this end of the adapter is the same size as the MALE vacuum hose. See pictures above. Although I will lose a significant amount of airflow in cubic feet ex - in short, I believe the vacuum will still outperform a shop vacuum at picking up fine dust. So when using this adapter, remember that it must have a fitting that matches the size of the tool (slot, brush, straight tube) it can be inserted into.