Burgtec 104mm BCD Inside Fit E-Bike Steel Thick Thin ChainringThe perfect, steel, e bike thick thin chainring for maximum chain retention and durability. Works with Shimano and SRAM Eagle 12 speed but not SRAM T Type. Comes in Burgtec Black only. Note: All Shimano motors use outside fit and most other e bikes use inside fit, however this is subject to change depending on the spider used. Bolt holes are threaded, 8mm x 0. 75mm x 8mm Long chainring bolts are required and included.