How to buy the mugen cover. Go to https://www.mugen-power-batteries.co...backdoor.html# and order HLI-N900XL, dont worry about if you never have ordered a mugen battery they don't check, as of now i have got 3 covers and i have never bought any mugen battery's ever. HtheB wanted to add that if you use the voucher code FACEBOOKSPECIAL you get a 7% discount (this if for everything on the mugen website, not just the XL-Cover)