●INCLUDES 3 VF3500 3-Layer Fine Dust replacement filters and 1 small brush to help trap particles that could harm the motor and decrease performance. ●COMPATIBILITY: Compatible with RIDGID vacs 3 gallon models #: WD3050. // 4 gallon models: WD4050, WD4070, WD4080, 4000RV(50313). // 4.5 gallon models: WD4550, WD4522, 4500RV(50318). ●Ideal for capturing, cold ashes, drywall sanding and fine powders. ●QUICK INSTALL: Place filter on top. Press down near the center of the filter with both thumbs until the rubber opening of the filter locks in securely, no tools or hardware needed. ●Change filter when vacuum performance decreases, when your vac has a clogged or dirty air filter it can cause it to work harder which will end up hurting your electric bill.