Waldin 7in1 Cot Extension SetTo further enhance the versatility of your Waldin 7in1 cot, you have the option to buy an additional extension set that allows for use up to 10 years. This set comprises the necessary assembly and mattress components to further transform the children's bed. This set consists of mattress extension and wooden extension part needed for expansion of Waldin 7in1 Square Cot and Waldin 7in1 Oval Cot.