And its the optics ready variant with the lower profile fsb, which means I bet you could get some of the wider diameter rails to go over the fsb. Have to use the code GLADTOMEETYOU630 for 20% off.
http://woodburyoutfitters.com/smith-wesson-m-p-15-sport-ii-semi-auto-rifle-10159-10159/
https://gun.deals/product/smith-wesson-mp-15-sport-ii-39999-code-gladtomeetyou630
http://woodburyoutfitters.com/smith-wesson-m-p-15-sport-ii-semi-auto-rifle-10159-10159/
https://gun.deals/product/smith-wesson-mp-15-sport-ii-39999-code-gladtomeetyou630