Yes, R&D is an interesting area. We have, I think most importantly, we've been doing this for 8 years, and we've learned a lot and we're into another generation on packs that really brings better features for the customers and lower costs. And however, at the same time, even the industries we're in, there are just continue to be a number of opportunities to expand offerings, maybe fill in some gaps. I mean, there's something like four different types of forklift. So fill in some of those gaps. There's a few gaps to fill in as well. And the timing of our R&D, we don't see R&D expense declining over time. We can have a little again, it is the word lumpiness, but a lot of its driven by well, how much are we testing? How much do we have some expensive product development costs in a quarter versus another quarter. And as we plan to grow, you go back to our strategy, and is to be a leader. To be a leader, we do need to build scale, we're building it. We have first mover positioning, and growing as fast or faster, and anybody I know, in this sector, and we want to continue to do that. To continue to service those customers on that slide, those are Fortune 500 customers with hundreds, thousands of packs, and we have to be able to provide to address all their needs from cost of service, serviceability, ease of doing business, and on and on to telemetry and so forth. And the -- our strategy to do that is to grow in sensible factors that satisfy our business cases that hopefully leverage the infrastructure we have, channels to market. And as we grow beyond that, we will do that at the pace that we can be successful. The demand is there. We've had more requests to go into this and that whether it's golf carts, you name it. hockey arena equipment, Zamboni [ph], so you could go on and on. And our challenge, and given the experience is to choose those that are going to be make sense, leveraging the resources we have and building that scale. Chuck, do you have anything to add on the R&D expense, because it's a good -- Amit has got a question there.