Material is 96% lead, 4% antimony; 4 counterbore holes at each corner, 1.125 center from side edge, 1.625 center from end.
No other part numbers with same form, fit, and function found.
NSN 6320-01-289-0946
NSN 6620-01-195-6675
NSN 6645-01-496-0073
NSN 7035-00-185-8683
NSN 5999-00-922-8368
NSN 6130-00-740-3884
NSN 2925-00-964-7128
NSN 6610-00-225-9886
NSN 6130-00-470-5195
NSN 5960-01-076-3936
NSN 6610-01-011-0296
NSN 6105-01-274-8865