DeWalt 20V to Black and Decker 18V Battery Adapter
Amazon.com: 1x Adapter Only Fits Black & Decker Fits Porter Cable 20v MAX (Not Old 18v) Tools Compatible with DeWalt 20v MAX Li-Ion Battery - Adapter Only : Tools & Home Improvement
1x Adaptor Fits DeWalt 20V XR Battery To Black & Decker 18v Old Style Type Tools | eBay