i didnt see the shank size of the 6 1/4, but as you can see the dewalt has a 3/8" shank

look for something like this
Amazon.com: DeWalt DW304PK Heavy-Duty 10 Amp Reciprocating Saw: Home Improvement

or get a little kit like this
Amazon.com: DeWalt DW304PK Heavy-Duty 10 Amp Reciprocating Saw: Home Improvement