4-Pack Danly Die Springs. 

SPRG.1.250X3.50-RED-HVY-DUTY

Wire Type: Rectangular

A - Hole Diameter: 1 1/4(in) 32(mm)
C - Free Length: 3.50(in) 89(mm)

Spring Constant: 80.10(lbs per 1/10in) 140.0(N/mm)