Just in stock at RSOV.com is an eM500A CREE Handguard weapon light which is specifically made for the M4 AEG. Made of ABS and fit to replace your existing M4A1 handguard, it throws 190 lumens with 3 CR1234 batteries which are not included in the package. This costs US$64.99 with an additional US$15.00 for shipping.