active power filter filter

revoling leaf type filter + vacuum filter

16 multislice helical CT

16-detector row helical CT

16-slice helical CT scanner

64 multi-detector helical CT

64-slice helical CT

64-sliees helical CT

conic logarithmic helical line

cross helical gear

double helical chain

Double Helical Gear

Double helical ribbons impe

Double-row helical CT

Driven helical bevel gear

dynamic pitch helical

eccentric annulus helical flow

enhanced helical CT

gear helical

heat exchanger pipe with continuous helical baffles