- Many Versions: Custom sizes for different mag well sizes to ensure proper fitment in different models of firearms. - Vise Compatibility: The base of these blocks are designed to fit into a vase with the flared portion resting above the clamp. - Mag Catch Latch: The mag catch / mag release of the firearm is engaged to hold the receiver and block together. - Thick and Sturdy: Printed with durability in mind. No low infill here. You can drop this, use it as a hammer, etc. - Original, Innovative Design: 1800+ products designed and 3D printed in the heart of America in St Louis, Missouri by Hammy3DPrints. MATERIAL: 3D printed using PLA+ filament.INSTALLATION: Put block into vise and clamp it. Then mount firearm onto the block.WARRANTY: If this item breaks I will make any design adjustments, if needed, and send a replacement for free.Made in USA. Please note that the products may have slight imperfections as 3D Printing is rarely perfect. The exact product you receive may also slightly vary from the product photos as I iterate and improve upon designs based on user feedback.