SPS Technologies will lay off about 250 employees — nearly half the workforce — weeks after a fire gutted its aerospace fastener factory outside Philadelphia, Manufacturing.net reports.

The average SPS employee has spent 25 years with the company. SPS offered the affected employees four weeks of compensation while it considers a rebuild.

SPS parent company Precision Castparts, owned by Berkshire Hathaway, made the decision.

The February 17 fire at the 105-year-old SPS facility took several days to extinguish. The 600,000 sq ft factory served as a main supplier of fasteners for the aerospace industry, including Boeing, whose CEO Kelly Ortberg has said depended on the SPS location for numerous parts in its 787 and 737 jets. SPS also supplied fasteners for Blackhawk helicopters, F-15 fighter jets and other military aircraft.

The site provided nearly 15% of the U.S. aerospace industry’s fastener supply,  according to AeroDynamic Advisory Managing Director Kevin Michaels.