-Easily converts from a toddler to a twin bed -Running boards become steps to help little ones climb into bed -Roll bar has real working lights that automatically turn off after 2 minutes -Reading lamp on roll bar automatically turns off after 10 minutes -When bed is being used as a toddler bed, use a standard crib mattress (approximately 52" x 28" x 6"--not included ) -When bed is being used as a twin bed, use a standard twin mattress (not included ) -Age 15 months - 3 years when used as a toddler bed -Age 3+ years when used as a twin bed -Maximum weight limit: up to 200lbs. -Product Dimension:90.00'' L x 52.70" W x 56.80" H