ATO/ATC Fuse Block System, Integral Ground Bus Style. 6 circuit. Clear insulating cover with label recess for small format Blue Sea Systems? labels. Cover insulates all conductive parts, satisfying ABYC/USCG requirements. Tin-plated copper buses and fuse clips give 30-ampere rating per circuit. Accepts ATO and ATC fast acting blade type fuses and plug-in style circuit breakers.