Fantastic condition, congratulations! The first grouping is JR ?, 1916, II B. The date is the year when the helmet was accepted by the Regiment, II B is second Battalion. JR or IR stands for Infantry Regiment. Your only problem remaining, is the Regimental number which is almost gone. My advice....go outside on a sunny day, moisten the area with some saliva or a drop of water and use the sunlight to try and decipher the number.