All include Bulb # 71DPCLR. All in pairs. 5342197: For use on Power driven vessels under 20 meters. 5300589, 5300591: 1 mile visibility, for use on boats under 39'-4'' 5304625: 2 mile visibility, for use on boats under 39'-4'' 5305411, 5305886: 2 mile visibility, for use on boats over 39'-4'' 5300591: 7/8''H x 2-3/8''W x 4-1/4''L, #4 screw size 5305411, 5305886, 5304625: 1-5/8''H x 2-1/4''W x 3-1/2''L #8 screw size, 5342197: For use on Power driven vessels under 20 meters.