2 Batteries, 1 AlternatorNegative Ground4.5"L X 4.55"W X 2.52"H(114mmL X 116mmW X 64mmH)I/O Studs 1/4-28 ThreadBlue Aluminum Finned Heat Sink,Press Fit Diodes, Welded ConnectionsArco# BI-0702-4 Sierra# 18-6855