Energetic Armament EA27 Direct Thread Adapters 5/8x24 Stainless Steel
https://www.tandktactical.com/shop/853406008275-energetic-armament-ea27-direct-thread-adapters-5-8x24-stainless-steel-42078
https://www.tandktactical.com/web/image/product.template/42078/image_1920?unique=390f5d3
fits Industry standard 1.375"x24 thread
