P440 30-hour MS (3/8 x .014 x 48

P441 30-hour MS (5/16 x .015 x 42

P331 31-day Mainspring

MS259 Mainspring

MS280 Mainspring (80-155)

MS301 Mainspring (80-170)

MS257 Mainspring (80-186)

MS287 Mainspring (80-195)

MS302 Mainspring (80-230)

MS255 Mainspring (80-365)

MS285 Mainspring (80-435)

MS262 Mainspring (80-446)

MS290 Mainspring (80-451)

MS300 Mainspring (80-480)

MS296 Mainspring (80-485)

MS264 Mainspring (80-493)

MS260 Mainspring (80-501)

MS270 Mainspring (80-502)

MS253 Mainspring (80-504)

MS261 Mainspring (80-505)

MS274 Mainspring (80-506)

MS284 Mainspring (80-507)

MS289 Mainspring (80-508)

MS292 Mainspring (80-509)

MS293 Mainspring (80-510)

MS295 Mainspring (80-511)

MS297 Mainspring (80-512)

MS299 Mainspring (80-513)

MS304 Mainspring (80-514)

MS305 Mainspring (80-515)