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Lower Parts Kit | AR 15 Lower Part Kits or AR 10 Lower Part Kits from Brands like CMMG, Guntec & More | Free Shipping Available! — 1,649 products / 4,312 models

All Lower Parts Kits are not created equal. This critical component is mil-spec'd to be the very best. Whether you want a trigger or pistol grip these Lower Parts Kits are easy to assemble and the perfect addition to any modification. Enhance your lover receiver with a Lower Parts Kit featuring triggers, AR15 Barrels, hammers, disconnectors are more essential Gun Parts for your next build out. Machined from the highest-quality materials these Lower Parts Kits are compatible with most AR15 and variant lower receivers. Featuring top brands such as CMMG, Inc, Aero Precision, and Guntec USA a Lower Parts Kit is crucial to keeping your rifle running smoothly. Check out our Sale & Closeout Prices for even more great deals on the gear you want and need most. As always, OpticsPlanet is thrilled to offer their most valued of customers Free Shipping On Orders Over $49.image

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Image of Radian Weapons Talon Ambidextrous Safety Selector 2-Lever KIT made-in-usa-flag 2 models Radian Weapons Talon Ambidextrous Safety Selector 2-Lever KIT (262) As Low As (Save Up to 30%) $64.95 5% Bonus Bucks
Image of RISE Armament Lower Parts Kit Ar-15 Minus Trigger RISE Armament Lower Parts Kit Ar-15 Minus Trigger (46) List: $44.99 (Save 31%) $30.99 Blazin' Deal
Image of Geissele Ultra Duty Lower Parts Kit made-in-usa-flag 2 models Geissele Ultra Duty Lower Parts Kit (59) As Low As (Save Up to 22%) $147.90 Best Rated
Image of Kaw Valley Precision Stainless Steel Heavy Tungsten Buffer Kaw Valley Precision Stainless Steel Heavy Tungsten Buffer (22) List: $69.95 (Save 33%) $46.99 Best Rated
Image of Strike Industries AR Enhanced Lower Receiver Parts Less Trigger, Hammer and Disconnector Strike Industries AR Enhanced Lower Receiver Parts Less Trigger, Hammer and Disconnector (100) List: $55.95 (Save $2.00) $53.95 Blazin' Deal
Image of JP Enterprises SCS System Buffer Retainer Pin & Spring Kit JP Enterprises SCS System Buffer Retainer Pin & Spring Kit (52) List: $23.97 (Save 46%) $12.99 Best Rated
Image of Aero Precision AR15 Lower Parts Kit, w/No FCG/Trigger Guard/Pistol Grip made-in-usa-flag Aero Precision AR15 Lower Parts Kit, w/No FCG/Trigger Guard/Pistol Grip (113) List: $67.39 (Save 35%) $44.09 Blazin' Deal
Image of Strike Industries AR-10 Enhanced Lower Receiver Parts Less Trigger/Hammer and Disconnector Strike Industries AR-10 Enhanced Lower Receiver Parts Less Trigger/Hammer and Disconnector (21) List: $59.95 (Save 10%) $53.95 Blazin' Deal
Image of Geissele Standard Lower Parts Kit made-in-usa-flag Geissele Standard Lower Parts Kit (24) List: $78.52 (Save 25%) $59.00 Best Rated
Image of KAK AR-15 Carbine Buffer Tube Kit Mil-Spec KAK AR-15 Carbine Buffer Tube Kit Mil-Spec (5) List: $45.00 (Save 28%) $32.50 Best Rated
Image of AT3 Tactical FU-BAG AR-15 Lost Parts Kit AT3 Tactical FU-BAG AR-15 Lost Parts Kit (81) $11.99 Best Rated
Image of Primary Weapons Systems EBT Mod 2 End Plate and Castle Nut Primary Weapons Systems EBT Mod 2 End Plate and Castle Nut (112) List: $49.95 (Save 24%) $37.99 Best Rated
Image of TacFire A2 AR-15/5.56 Fixed Stock Kit TacFire A2 AR-15/5.56 Fixed Stock Kit (48) List: $64.99 (Save 22%) $50.99 Best Rated
Image of Strike Industries AR Enhanced Lower Receiver Parts with Trigger, Hammer and Disconnector Strike Industries AR Enhanced Lower Receiver Parts with Trigger, Hammer and Disconnector (68) List: $77.95 (Save $2.00) $75.95 Blazin' Deal
Image of KAK Industry AR-15 LPK Missing Parts Kit KAK Industry AR-15 LPK Missing Parts Kit (4) List: $9.00 $8.79
Image of Bravo Company Mil-Spec Carbine Stock Hardware Mounting Kit Bravo Company Mil-Spec Carbine Stock Hardware Mounting Kit (40) List: $65.00 (Save 11%) $57.95 Best Rated
Image of Rise Armament OPMOD Hex-C RA-240 AR-15 Enhanced Rifle Trigger and Lower Parts Kit Rise Armament OPMOD Hex-C RA-240 AR-15 Enhanced Rifle Trigger and Lower Parts Kit (31) List: $214.99 (Save 40%) $128.99 Blazin' Deal
Image of RISE Armament OpticsPlanet Exclusive RAVE 140 With AR-15 Lower Parts Kit 2 models RISE Armament OpticsPlanet Exclusive RAVE 140 With AR-15 Lower Parts Kit (46) As Low As (Save Up to 38%) $110.99 Blazin' Deal
Image of TRYBE Defense LR-308 DPMS .308 Complete Bolt Carrier Group (BCG) 2 models TRYBE Defense LR-308 DPMS .308 Complete Bolt Carrier Group (BCG) (73) As Low As (Save Up to 44%) $111.99 Blazin' Deal
Image of Armaspec AR15 GEN4 H2 Stealth Recoil Spring Buffer Kit made-in-usa-flag Armaspec AR15 GEN4 H2 Stealth Recoil Spring Buffer Kit (3) List: $120.99 (Save 10%) $108.89
Image of Strike Industries AR Picatinny Stock Adapters 2 models Strike Industries AR Picatinny Stock Adapters (24) As Low As (Save $2.00) $49.95 Blazin' Deal
Image of Armaspec AR15 GEN4 H3 Stealth Recoil Spring Buffer Kit made-in-usa-flag Armaspec AR15 GEN4 H3 Stealth Recoil Spring Buffer Kit (3) List: $120.99 (Save 10%) $108.89
Image of Strike Industries AR Anti-Walk Pins Strike Industries AR Anti-Walk Pins (39) List: $21.99 (Save 27%) $15.99
Image of Radian Weapons Talon Ambidextrous 45/90 Safety Selector Combo 2-Lever KIT made-in-usa-flag 2 models Radian Weapons Talon Ambidextrous 45/90 Safety Selector Combo 2-Lever KIT (40) As Low As (Save Up to 15%) $62.96 Blazin' Deal
Image of Armaspec AR15 Gen4 C/H/H2 Stealth Recoil Spring Kit made-in-usa-flag Armaspec AR15 Gen4 C/H/H2 Stealth Recoil Spring Kit (20) List: $109.99 (Save 10%) $98.99 Best Rated
Image of Hogue AR15/M16 Kit, Beavertail Grip and OverMold Collapsible Buttstock made-in-usa-flag 8 models Hogue AR15/M16 Kit, Beavertail Grip and OverMold Collapsible Buttstock (398) As Low As (Save 24%) $53.51 Blazin' Deal
Image of Vltor A5, Spring And Buffer Kit Vltor A5, Spring And Buffer Kit (17) List: $65.95 (Save $5.96) $59.99 Best Rated
Image of Real Avid AR-15 Armorers Master Kit Pro Real Avid AR-15 Armorers Master Kit Pro (9) List: $620.00 (Save 15%) $529.99 Best Rated
Image of KAK AR-15 Configurable Buffer Kit KAK AR-15 Configurable Buffer Kit (13) List: $47.00 (Save 10%) $42.30 Best Rated
Image of Aero Precision AR15 Carbine Buffer Kit made-in-usa-flag Aero Precision AR15 Carbine Buffer Kit (90) List: $75.00 (Save 18%) $61.19 Blazin' Deal
Image of Aero Precision M5 .308 Rifle Buffer Kit made-in-usa-flag Aero Precision M5 .308 Rifle Buffer Kit (51) List: $85.00 (Save 18%) $69.29 Blazin' Deal
Image of Tippmann Arms M4-22 ELITE .22 Long Rifle, 16in Conversion Upper Receiver Kit Tippmann Arms M4-22 ELITE .22 Long Rifle, 16in Conversion Upper Receiver Kit (2) List: $379.95 (Save $30.00) $349.95
Image of FM Products Glock Style 9mm 5 inch AR Rear Charging Builders Kits FM Products Glock Style 9mm 5 inch AR Rear Charging Builders Kits (2) List: $499.00 (Save 12%) $439.49 Blazin' Deal
Image of FAB Defense M4 Collapsible Stock Optics-Ready Pro Kit For Ruger 10/22 4 models FAB Defense M4 Collapsible Stock Optics-Ready Pro Kit For Ruger 10/22 (17) As Low As (Save Up to $19.81) $204.49 Blazin' Deal
Image of JP Enterprises Complete JPBC Bolt Carrier Group (BCG) 5 models JP Enterprises Complete JPBC Bolt Carrier Group (BCG) (24) List: $485.00 Add to Cart for Your
Special Price 10% Bonus Bucks
Image of Matador Arms MAT-9 AR-9 9mm 7.825in Roller Delayed Upper Receiver 3 models Matador Arms MAT-9 AR-9 9mm 7.825in Roller Delayed Upper Receiver List: $599.00 (Save $24.00) $575.00 Newly Added
Image of Radian Weapons AR15 Takedown Pin Kit made-in-usa-flag Radian Weapons AR15 Takedown Pin Kit (21) List: $51.63 (Save 24%) $39.49 10% Bonus Bucks
Image of Armaspec Spare Parts Kit made-in-usa-flag Armaspec Spare Parts Kit (23) List: $25.03 (Save 36%) $15.99 Best Rated
Image of Bravo Company AR-15 Enhanced Lower Parts Kit 2 models Bravo Company AR-15 Enhanced Lower Parts Kit (67) List: $130.00 (Save $11.05) $118.95 Best Rated
Image of Volquartsen Firearms OpticsPlanet Exclusive Ruger 10/22 Automatic Bolt Release and Bolt Tune-Up Kit Bundle Volquartsen Firearms OpticsPlanet Exclusive Ruger 10/22 Automatic Bolt Release and Bolt Tune-Up Kit Bundle (6) List: $48.00 (Save 38%) $29.99 Blazin' Deal
Image of Cry Havoc Tactical 223 Two Pin QRB Kits 4 models Cry Havoc Tactical 223 Two Pin QRB Kits (7) As Low As (Save Up to $25.01) $489.99 Free 2 Day Shipping
Image of Aero Precision M5 .308 Enhanced Carbine Buffer Kit made-in-usa-flag 3 models Aero Precision M5 .308 Enhanced Carbine Buffer Kit (35) List: $115.00 (Save 18%) $94.49 Blazin' Deal
Image of Matador Arms MAT-9K AR-9 9mm 5in Roller Delayed Upper Receiver 3 models Matador Arms MAT-9K AR-9 9mm 5in Roller Delayed Upper Receiver List: $599.00 (Save $24.00) $575.00 Newly Added
Image of Maxim Defense Industries MDX 505 PDX SCW PDW Brace Upper Kit made-in-usa-flag 6 models Maxim Defense Industries MDX 505 PDX SCW PDW Brace Upper Kit (7) List: $1,795.00 (Save Up to 12%) $1,615.50 Best Rated
Image of Matador Arms MAT-916 AR-9 9mm 16in Upper Receiver Matador Arms MAT-916 AR-9 9mm 16in Upper Receiver (1) $585.00
Image of CMMG AR-15 ZEROED Gunbuilder's Lower Parts Kit CMMG AR-15 ZEROED Gunbuilder's Lower Parts Kit (20) List: $89.95 $89.29 Best Rated
Image of Radian Weapons Talon Ambidextrous 45/90 Competition Safety Selector 2-Lever KIT made-in-usa-flag Radian Weapons Talon Ambidextrous 45/90 Competition Safety Selector 2-Lever KIT (15) List: $79.97 (Save 13%) $69.95 5% Bonus Bucks
Image of FAB Defense UAS-PRO Ruger 10/22 UAS Precision Stock Conversion Kit 4 models FAB Defense UAS-PRO Ruger 10/22 UAS Precision Stock Conversion Kit (10) As Low As (Save Up to 12%) $180.49 Blazin' Deal
Image of Armaspec Carbine Buffer Tube Kit w/End Plate and Castle Nut made-in-usa-flag Armaspec Carbine Buffer Tube Kit w/End Plate and Castle Nut (2) List: $38.99 (Save $1.00) $37.99
Image of Zaffiri Precision Glock 43 ZPS.3 Threaded RMSc Cut Complete Upper 2 models Zaffiri Precision Glock 43 ZPS.3 Threaded RMSc Cut Complete Upper (2) List: $559.99 (Save 11%) $499.99 Free 2 Day Shipping
Image of Sharps Bros. AR-15 Billet Stripped Upper Receiver w/Forward Assist Sharps Bros. AR-15 Billet Stripped Upper Receiver w/Forward Assist (3) List: $229.95 (Save $16.20) $213.75
Image of R&D Precision PW9 9mm Gen 1 Bufferless Upper Kit R&D Precision PW9 9mm Gen 1 Bufferless Upper Kit (15) List: $559.99 (Save 11%) $499.99 Best Rated
Image of Aero Precision Enhanced Carbine Buffer Kit made-in-usa-flag 4 models Aero Precision Enhanced Carbine Buffer Kit (70) As Low As (Save Up to 19%) $69.29 Blazin' Deal
Image of Strike Industries PDW Stock 2 models Strike Industries PDW Stock (33) List: $274.95 (Save $15.00) $259.95 Best Rated
Image of Kaw Valley Precision AR-10 6 Position CAR Stock Completion Kit Kaw Valley Precision AR-10 6 Position CAR Stock Completion Kit (8) List: $67.95 (Save 13%) $58.99 10% Coupon
Image of Guntec USA AR .308 Gen 2 Complete Pistol Upper Kit Guntec USA AR .308 Gen 2 Complete Pistol Upper Kit (2) List: $799.00 (Save 29%) $569.99 On Sale
Image of KAK AR-15 Lower Parts Kit KAK AR-15 Lower Parts Kit (45) List: $55.00 (Save 19%) $44.50 Best Rated
Image of Daniel Defense Buttstock, Pistol Grip & M-LOK Vertical Foregrip Combo 2 models Daniel Defense Buttstock, Pistol Grip & M-LOK Vertical Foregrip Combo (9) List: $152.00 (Save $12.00) $140.00 Best Rated
Image of Zaffiri Precision Glock 43 ZPS.2 RMSc Cut Complete Upper 2 models Zaffiri Precision Glock 43 ZPS.2 RMSc Cut Complete Upper (3) List: $559.99 (Save 11%) $499.99 Free 2 Day Shipping
Image of Kaw Valley Precision AR-10 CAR SS Tungsten Buffer Kaw Valley Precision AR-10 CAR SS Tungsten Buffer (4) List: $59.95 (Save 43%) $33.99 10% Coupon
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