AAR Wheel Arrangement - (B+B-B+B)+(B+B-B+B)

(B+B-B+B)+(B+B-B+B)

"(B+B-B+B)+(B+B-B+B)" means there are 2 units, each with 4 trucks in a B+B-B+B wheel arrangement. Example include the Virginian Railway's EL-2B electric locomotives.

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