filter cap

side cap; garrison / flight cap (US); wedge cap (Canada); field service cap (UK)

band-pass filter / bandpass filter (BPF)

dust filter / dust shield, particle filter

dust shield / dust filter, particle filter

filter housing / filter unit

filter unit / filter housing

particle filter / dust shield, dust filter

finite impulse response filter (FIR-filter)

passband filter; bandpass filter (BPF)

base cap

cap adapter

cap well (mine, IED)

capability catalogue (CAP CAT)

cap-comforter

combat air patrol (CAP) aircraft

detonating cap

dust cap

field cap

fighter cap/ umbrella

forage cap

fuse cap

garrison cap

locking cap

percussion cap

summer cap

sailor cap

cap retaining pin

cap retaining pin bushing

cap retaining pin bushing assembly

cap retaining pin screw

cap retaining pin spring

deflector cap