Modulus Arms was founded by AR enthusiasts with highly technical engineering backgrounds. Our products are designed for ease of use with the end-user in mind, and employ decades of engineering experience. We believe our 80% Lower AR Jigs and related accessories are amongst the highest quality on the market, with unmatched functionality and fitment.

Our customer support team understands the importance of post-sale support, and aims to educate our customers on how to get the most out of their Modulus Arms products. Our mission has always been to take the guess work and hassle out of fabricating 80% lowers.

We have achieved success through expert product design and simplifying the end-user fabrication process, while maintaining the perspective of being enthusiasts ourselves.