Midwest Industries MIMGB750 Micro Gas Block 4140 Steel .750"
https://www.tandktactical.com/shop/816537011545-midwest-industries-mimgb750-micro-gas-block-4140-steel-750-17834
https://www.tandktactical.com/web/image/product.template/17834/image_1920?unique=a61b459
The Micro Gas Block from Midwest Industries is designed to fit under most commercially available handguards on the market.