Check the listing for details. 1 Thompson Center FLINTLOCK MODELS Mainspring Hawken NOT PERCUSSION Muzzleloader. Condition: New. Listed at 24.99 USD. FREE COMBINED SHIPPING when you buy more, so check out my other muzzleloader listings. STOCK UP and SAVE! Go to my store or sellers other items and type in muzzleloader to see more! One New Thompson Center Flintlock Mainspring. Fits all models of TC flintlocks. Will NOT fit percussion without modification. Very difficult to source these springs so stock up before they're gone! We pride ourselves in offering a variety of quality production, custom and aftermarket replacement parts and supplies for black powder builders, shooters and enthusiasts of any level. Free Combined Shipping from the highest shipping cost, all on the same order. If you buy a tang screw with $5 shipping and a barrel with $25 shipping, you will only pay $25 shipping so add patches, flints, screws, springs, jagsit will all ship for $25. If you use the buy it now or auto-pay function, just reach out when you're done shopping and we'll refund accordingly.