Used on M551. 3.880" overall length 3.880" overall width pmtg holes 2.000 apart centered ontongues 0.880 w 1.240 apart; cross-sectional aperture 3.500 x 3.500 through; connector accommodation 2.310 dia w/4 holes 0.148 dia equally spaced on 2.625 dia bolt circle; color white enamel surface treated irregular