QUIETER OPERATION: Vac muffler diffuser helps reduce air noise for quieter operation REDUCES BLOW BACK: Diffuses wet dry vacuum airstream to reduce blowing debris and dust EASY INSTALLATION: Connects to the blowing port of the shop vac INDUSTRIAL-GRADE CONSTRUCTION: CRAFTSMAN wet dry vacuum attachments are built to handle heavy use FITS: CRAFTSMAN wet/dry vacs with a 2-1/2 in. blowing port