The Garmin EDGE 520J is a GPS/GLONASS-compatible cycle computer with a 3.5-inch display and Bluetooth functionality. - Model: EDGE 520J - Bluetooth: Yes - GPS: GPS/GLONASS compatible - Display Size: 3.5 inches - Water Resistance: 60% water resistant - Size: 4.9 x 3.3 x 2.1 cm - Price: ¥49,800 As of this summer, the battery lasted about 5-6 hours with a heart rate monitor, speed sensor, and cadence sensor connected via Bluetooth, without using a power meter or Di2. I expect it to be worse in the winter. I replaced the battery pack with a new one, but it didn't make much difference. For safety, I've included a new spare battery. Everything in the images is included, so please note that sensors are not included. Please use it for short rides or for parts. Junk item.