RX (Generic)Nivaflex automatic mainsprings for wristwatches (Bestfit)Nivaflex mainsprings from Boley for automatic winders. Products namewidthØthicknesslengthcalibreitem No.3156x1.277.750,071440RX 2130/2135 (Generic)820315602825x1.1611.20.115455RX 3130/3135/3155/3175/3185 (Generic)820282503077x1.2412.50.146490RX 4030 (Generic)820307703092x1.257.50.085315RX 2030/2035 (Generic)820309201160-7701.256.500.07280RX 1160 (Generic)9810077011603318x1.3011.00.12460RX 1520/1530/1570 (Generic)820331803676x1.4011.20.10560RX 3000 (Generic)820367603692x1.4011.80.106530RX 3030/3035/3055/3075/3085 (Generic)820369203992x1.4511.80.112565RX 4130 (Generic)820399204027x1.4610.00.72370RX 2230/2235 (Generic)82040270