War Hammer Armaments only supports the Super Safety on Lee Sporting Lowers. We do not warrant, endorse, guarantee compatibility, or claim affiliation with any 3D-printed or third-party receivers. Use outside of a Lee Sporting Lower is at your own risk and not covered under warranty.

All WHA Super Safety components are manufactured to at least TDP (Technical Data Package) standards per the U.S. Department of Defense’s Colt M16/M4 specifications. Each unit is hand-inspected and quality checked prior to packaging. If you’re experiencing bolt binding, it may indicate incompatibility with out-of-spec components or improper installation.

Each Lee Sporting Lower comes with a fitment kit containing:

• 1 foam insert

• 1 small shim

• 1 medium/large plastic shim

These components may require minor fitting adjustments to ensure a snug connection and eliminate any play between the upper and lower. Please reference the included instructions for proper installation.

On the WHA website, after selecting your MP5 model and barrel length (e.g., MP5 or MP5K where K = short & MP5 = standard length), you’ll be prompted to choose the appropriate lower receiver based on platform compatibility. The dropdown will specify either:

• HK/PTR

• All Others

Please select according to your specific MP5 platform.

If something is missing from your order, please email WHA with:

• Your 4-digit invoice number

• A clear photo showing all the received components laid out

• A note specifying which part you believe is missing

We will promptly verify the issue and ship the missing component at no additional charge.

Yes! If the website lists a specific quantity in stock, that is the accurate, live inventory. If an item is out of stock but still allows you to add it to your cart, it means the item is available for backorder. Backordered items typically ship within a reasonable timeframe, and we strive to keep delays minimal.