Spring for 21A1774 valve. Last Genuine few from AP.
11 coil 15swg and gives 35-42.5lbs pressure at fitted length of 0.98".
The only difference in the 21A2031-21A1774 valves is the spring length and poundage.
The spring for 21A2031 is 37H2009 where the Reg valve Spring gives 28lbs / 32 lbs at 0.98” fitted length.