You need a special triangler screwdriver to change batteries on Brio trains. : r/assholedesign
Triangle Head Screwdriver Set TA14 TA18 TA20 TA23 TA27 Brio Thomas Train toys | eBay
Full Triangle Head Screwdriver Set For Electronics Toys Security Screws Happy Brio Trains, TA14 TA18 TA20 TA23 TA27 TA30 - Walmart.com
Triangle Head Screwdriver Set TA20 TA23 TA26 TA30 Brio Thomas Train toys 117 Pcs | eBay
Amazon.com: Brio World - 33253 Stacking Track Supports | 2 Piece Toy Train Accessory for Kids Age 3 and Up, Green : Toys & Games
Triangle Head Screwdriver Set TA20 TA23 TA26 TA30 Brio Thomas Train toys 117 Pcs | eBay
Utoolmart Triangle Screwdriver, 2.3mm Magnetic Triangle Head Tip Screwdriver, 75mm 45# Steel Shaft, with 55mm Plastic Handle, for Repair Home Improvement Craft, 2 Pcs - Amazon.com
Amazon.com: Brio World - 33253 Stacking Track Supports | 2 Piece Toy Train Accessory for Kids Age 3 and Up, Green : Toys & Games