Dual bore annulus access valve

Dual bore riser

Dual bore well treating tool

Dual brake type drive mechanism

Dual bypass for piston-type flushometer

Dual camming action jaw assembly and power tong

Dual capacity flush valve assembly for a toilet

Dual capacity sink

Dual cell honeycomb structure

Dual chain equalizer for a drill string rotating mechanism

Dual channel downhole telemetry

Dual channel downhole telemetry

Dual check valve

Dual claw spike puller

Dual closure means for agricultural transport devices

Dual completion apparatus and method of positioning same in...

Dual completion well installation

Dual concentric pipe joint

Dual cone expander for expanding a tubular element to...

Dual containment pipe system and method of installation