Regarding SBHS-002T-P0.5 and SBHS-002T-P0.5A BHS series connectors
The difference is the width of the contact lance. The “A” style is the latest version with a lance that is about twice the width of the original contact (without the “A”).
The contact was modified and went into effect in April 2003 to improve contact retention within the housing and to help prevent accidental extraction and slippage of the contact from the housing.
As the contact lance has been modified, so has the applicable housing. The housing to be used with contact SBHS-002T-P0.5A is part number BHSR-02VS-1 formerly numbered BHSR-02VS-1(N) which is listed at the bottom of the product page within “Other Names”. The (N) indicates a modification of the housing lance to accommodate the contact with the modified lance. Similar to above housing number, this may be an older suffix most likely not used or listed under Other Names.
See also:
Source - https://www.jst.com/resources/faq/
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