What Knight's Armament Products Does OperationParts.com Carry?

OperationParts.com carries Knight's Armament (KAC) products across three main categories: complete rifle systems, upper and lower receiver build kits, and small accessories like handguard panels and optic mounts. If you're deciding between a full SR-15 rifle and building one from a kit, the site lists both, with prices ranging from about $28 for a handguard panel up to roughly $5,024 for a high-end SR-25 upper kit. Note that at least one KAC item shown on the homepage — the SR-15 IWS Lower Build Kit (BLEM) — is currently out of stock, so availability varies by product.

Complete KAC Rifle Systems

The site lists factory-built KAC rifles as standalone products. The clearest example is:

This is a complete 5.56 rifle in the SR-15 line. If you want a turnkey KAC gun without sourcing parts separately, this is the direct option.

Upper and Lower Receiver Kits

For builders, OperationParts.com lists KAC receiver kits that let you assemble or upgrade a rifle around a KAC upper or lower:

• KAC-Knight's Armament SR-15 IWS Lower Build Kit BLEM — $648.00. Listed as a blemished (cosmetic second) lower build kit. Currently out of stock.
• KAC-Knight's Armament SR-25A3 Upper Receiver Kit, 22″ Barrel — $3,456.00 to $5,024.25 depending on variant. This is a large-frame (.308/7.62-class) upper kit, positioned well above the SR-15 line in both price and caliber.

The SR-15 kits sit in the small-frame 5.56 category, while the SR-25A3 upper is a large-frame platform. That caliber and size difference is the main reason the SR-25 kit costs several times more.

KAC Accessories and Small Parts

Beyond rifles and kits, the site stocks KAC-branded accessories, including:

• KAC-Knight's Armament 5 Rib Handguard Panel, 3.47″ Length — $27.99, with multiple variants selectable.
• KAC-Knight's Armament Leupold Delta Point Pro Modular Scope Cap Attachment — $218.81, an optic accessory for mounting a Delta Point Pro.

These are the low-cost entry points into KAC parts if you already own a compatible rifle and just need panels or optic hardware.

How to Choose Between the KAC Lines

Use these conditions to decide:

• Want a complete, ready-to-run 5.56 rifle: the SR15 KS4 Rifle System at $2,999.52 is the direct pick.
• Building or upgrading a 5.56 rifle and want KAC parts: the SR-15 IWS Lower Build Kit fits, but confirm restock first since it's out of stock.
• Need a large-frame (.308-class) upper: the SR-25A3 Upper Receiver Kit is the relevant product, with the price depending on which variant you select.
• Only need small KAC accessories: handguard panels (~$28) and optic attachments (~$219) are available without buying a full rifle or kit.

Practical Notes Before Ordering

• Prices shown are per the site's product listings and vary by variant for items with selectable options (the SR-25A3 kit and the handguard panel both have multiple variants).
• Stock status is product-specific. The SR-15 IWS Lower Build Kit BLEM is marked out of stock, so check each listing rather than assuming availability.
• The site organizes KAC and other brands under rifle, shotgun, pistol, sights, mags, and accessories categories, so you can browse by platform if you're not sure which KAC part fits your build.