Mike,Does the key have Leedy engraved on it? For the most part, Leedy always engraved or stamped their keys with their name...However, there are exceptions to this rule...If it is stamped, the key is worth quite a bit...I've seen them go as high as $150 in auction on ebay...Of course, that is most likely a collector bidding...;) If it isn't, then it could be worth a little less to a collector...That is the correct style key for the older Leedy slotted rods...It should fit perfect in the slot...Sometimes, people like to use Robertson screwdrivers and such to adjust the tension on drums with slotted rods...Needless to say that we all know what happens over time to the heads of the rods when the proper key isn't used...Definitely a nice score, Mike...Congrats!! I would keep everything together...Cheers