Sig Sauer Mainspring Seat, P220/6/9 $12.50 Plastic Mainspring Seat, P220, P226, P229. Factory replacement mainspring seat, Sig Part: Mainspring-seat-1 Out of stock Category: Sig Sauer Related products Sig P226/228/229 XP magazine springs 3 pak $34.97 Sig Sauer P220 / P226 Variable Recoil Spring 15lb. $14.97