It uses a regular hinge skull design aimed at reducing pressure behind the ears, sized at (best for medium to large face shapes). Aesthetics:
The terminal block supports:
Decomposes in soil water or may volatilize from dry surfaces
: Typically indicates a new version0;8da; , a "new old stock" item, or a revised instruction set for a pre-existing part. 0;2a;
(Example table to use when comparing 3+ options — provide specifics if you want actual parts compared.)
Here is a solid review of the NGK/NTK NO2 Sensor (LMVV038):