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The shop vacuum I own is the Ridgid WD4050, bought at Home Depot. It has good suction and takes a HEPA filter, which is important in this application.
This unit is no longer sold but has been replaced by a very similar model.
It's significant defect, continued in the current model, is that the hose diameter (1 7/8 inches) is completely nonstandard. It will only accept the few attachments made specifically for this model.
There are no fittings or adapters (including the rubber multi-diameter type) which will fit this diameter hose. It cannot be attached to the dust collection ports on any power tools.
For that reason, in order to attach the vacuum hose to the sanding box, I had to purchase the compatible crevice tool and saw off the nozzle, leaving the fitting.
With any luck, your vacuum is the more common 1 1/2 or 2 inch diameter and you can find an off-the-shelf fitting.