All of the S version of the batteries come with brass automotive terminals. All of the S versions also come with metal protective cases (EXCEPT FOR THE S3400) for added under the hood protection. The S3400 DOES NOT come with a metal protective case. The D version batteries do not come with auto terminals, but they do come with the bolts and washer to use with ring terminals. Automotive terminals can be purchased separately (part number # 580 or 586) for these versions. So, if you are going to use the battery under the hood I would suggest buying the S version, but if you are going to use it as a secondary battery the D version would be more economical.