Hi Andrew,
Thanks for your response. Sorry for being vague - I am new to bike repair and working my way up up the learning curve. There is no model number on the crank arms or chainrings that I can see. Looking at the outer/ largest chainring, I see 4 bolt on the outer edge of the chainring. Those bolt holes are empty. Looking at the middle of the outer chainring, there are 4 bolt holes which are bolted to the middle chainring. Looking at the smallest/ inner chainring, there are also 4 bolt holes. The bolts shoot through all 3 chainrings. The crank arms are as far as I can see bolted onto the outer chainring. They look a lot like the AKA crankset on the SRAM website, thought my set was purchased new in 2010.