20v max battery adapter for 18v tools, compatible with most dewalt 18v tools, makes it possible to use new dewalt 20v max lithium technology on 18v nicad tools, requires use of dewalt 20v max charger, adapter will not fit into dewalt 18v chargers, battery & charger are sold separately, do not use adapter with premium batteries dcb200, dcb204, dcb204bt & dcb205 in 18v compact drills dc970, dc759, use with dcb201, dcb203, dcb20bt3bt compact batteries.