The San Tan Tactical STT-15L Lite Pillar billet lower receiver (San Tan part no. STT-15L-LT-LWR) is a lightweight AR-15 pattern lower machined from 7075-T6 aluminum. San Tan Tactical designed the STT-15L for 3-gun, hunting and any build where weight matters, and the receiver weighs just 7.7 ounces. It keeps the Pillar look with truss pockets, a flared magazine well and a shooter-ready finger rest. The lower accepts mil-spec AR-15 and M16 components and lower parts kits, apart from the included ambidextrous controls.

Key Specifications

• The receiver is machined from billet 7075-T6 aluminum, an aerospace-grade alloy.
• It weighs 7.7 ounces, a significant weight reduction compared with the standard STT-15.
• The finish is Mil-Spec MIL-A-8625 Type III Class II hard anodizing.
• The listed caliber is 5.56/.223, matching standard AR-15 builds.
• The magazine well has a 1.38-inch integrally machined flare for faster reloads.
• The lower has truss pockets that add rigidity while removing weight.
• Bullet pictogram safety selector markings make the fire and safe positions easy to read.
• An oversized winter trigger guard leaves room for a gloved hand.
• Controls use ultra-grip texture, and the lower includes ambidextrous controls.
• The receiver is Made in the USA with a lifetime warranty from the maker.

Frequently Asked Questions

How much does the STT-15L lower weigh? San Tan Tactical lists the STT-15L lower at 7.7 ounces.

Does it work with standard AR-15 parts? Yes. It accepts mil-spec AR-15 and M16 components and lower parts kits, excluding the included ambidextrous controls.

What is the receiver made from? It is machined from a billet of 7075-T6 aerospace-grade aluminum and hard anodized.

Buy the San Tan Tactical STT-15L Lite Pillar Billet Lower Receiver

The STT-15L is a lightweight billet lower for builds that count every ounce. Order it from our Lubbock, Texas gun shop for fast, insured shipping to your FFL, and browse more AR-15 lowers while you are here.