Lot of 4 items for final version of this club kit. Mailing envelope is 6x9" w/return address. One of 4 versions and only design featuring images of the club badge. Typical wear from mailing. Fine. 5.5x8.5" letter w/printing in dark blue mentions items included w/kit and that coded messages appear in "All-Star Comics." Has facsimile signature of secretary "Diana Prince (Wonder Woman)." Letter is one of 4 varieties, and the only one w/o a postscript (PS). Sheet has very lt. aging but has not been folded. VF. 8.5x11" certificate w/typed name/address of original recipient on provided lines plus penciled signature and typed individual issue number. This came in 5 varieties w/hero portrait images varying from certificate to certificate. This is only variety to show Batman, Superman and Black Canary. Also of note - all other hero portraits w/exception of Flash feature different images than from earlier issues. Has horizontal fold at center as issued. Exc. The "Top Secret" decoder is 3.75x9" on stiff bw paper and one of 3 designs, this being the only one in this format as opposed to the more common round disc. Unused and has not been folded along center scored line. St. edge wear, top half has some tiny pinpoint indentations caused by badge laying against it. VF. Rare club kit.