The phil&teds doubles kit is a second seat attachment designed to adapt your inline buggy to meet the needs of your growing family. Attach this doubles kit to the front or back of your phil&teds Navigator buggy and convert your single stroller into a double stroller. The doubles kit features a 2-postion, one-hand recline, comfortable seat liner, 5-point safety harness, a sun canopy and is meant for use from 4 months up to 4 years or the maximum load of 33 pounds (installed on back) or 44 pounds (installed on front).