Personalized Ohm Tree Toddler Long Sleeve T-Shirt. A tree filled with the ohm symbol and edged in a bit of resistance is a fun winter holiday and Christmas gift design for electricians and electrical engineers. A classic for Fall, Winter and Spring, these long sleeve toddler t-shirts are sure to be a staple in your child's wardrobe. Whether layered or alone, this t-shirt is soft yet durable enough to stand up to your toddler's playtime demands.