We’ll compare Shark NV402 and NV356E below to help you buy the better one that fits your needs.
NV402 vs NV356E
images from manufacturer
Headlights
This is one of the major difference between NV356E and NV402.
The Shark Rotator Professional NV402 has headlights to help cleaning dark areas while the Shark Navigator Lift-Away Professional NV356E has no headlights.
Lift Away Canister Design
This is another key difference. The NV356E features the Portable Lift Away Canister which allows you to carry the canister to clean around your house while the NV402 does not have this lift away feature.
Color
The NV356E is white with grey while the NV402 is white with red.
Hard Floor Attachment
The NV356E comes with a Dust-Away Hard Floor Tool with 2 Microfiber Pads for cleaning bare floors while the NV402 does not include.

Other Included Tools
The NV402 includes a Dusting Brush, 18-inch Flexi Crevice Tool, Turbo Brush, Wide Upholstery Tool, and Multi-Angle Dust Brush.

While the NV356E comes with a Dusting Brush, 8-inch Crevice Tool, 24-inch Crevice Tool, Turbo Brush.

Cleaning Path
The NV402 has a cleaning path of 10-inch while it is 9.5″ on the NV356E.
Weight
The NV402 is heavier than the NV356E.
Similarites:
HEPA filtration, Complete Sealed Technology, 10 amps, 30 foot cable, motorized brush with On/Off, pivoting head.
Download manuals to learn more before buying:
NV402 Owner’s Guide: http://www.sharkclean.com/rotator/pdfs/NV400-Owners-Manual.pdf
NV356E Manual PDF file: http://www.sharkclean.com/include/pdf/manual-NV356E.pdf
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