Ferraz Shawmut Semiconductor Current Limiting Fuse A70QS250-4 250a Amptrap

These semiconductor fuses cost hundreds of dollars new. You can search them out online to confirm. Just $20 here. They work as current limiting fuses. These are large size and roughly 1 pound each. They were all recovered from industrial battery packs. These seem like a ceramic style.

• 250 Amps, 700 Volts AC / DC
• Semiconductor Fuse
• Extremely Fast Acting
• Current Limiting
• Equivalent to Buss FWP Style
• Physical Size: 1.5" x 5.09"
• AC Voltage Rating: 700
• DC Voltage Rating: 700
• AC Interrupting Rating: 200,000 AIC
• DC Interrupting Rating: 100,000 AIC
• Very Low I²t For Improved Protection of Equipment
• Superior Cycling Ability, Low Watts Loss
• UL Recognized Component, AC/DC UL file E60314
• AC: Guide No. JFHR2
• DC Tested to UL Standard 198L Parameters (35-800A)
• CSA Certified File LR 12636