I was just about to order one of those fancy (and expensive!) quick-connect fittings to solve the problem of my vacuum hoses always pulling apart at the most inopportune moments. But then it occurred to me that a metal shelf pin might just do the trick. I connected the hose to one of my vac attachments, drilled a 1/4" hole through them both and wedged in a shelf pin. The pins have a long enough shank to lock the assembly together, yet they’re not so long as to protrude into the airstream and obstruct the airflow. They work well!