What does the bumpstop do? It's what cushions your car on the big bumps when you get to the end of your suspension travel. It's basically the last part of your suspension travel. Miatas - especially NAs and NBs - spend a lot of time on their bumpstops, so they're a pretty important part of the suspension. We think they're so important that we include a new set of stops with every set of shocks we sell. We worked with one of our polyurethane suppliers to come up with this extremely durable bumpstop. It has the same characteristics as our previous MCU units, but with a more consistent spring rate and longer life - without affecting the price. Strongly recommended for all 1990-97 Miatas as the stock bumpstops are terrible. The stock bumpstops on NB and NC Miatas are similar to our design, but suffer degradation with time and can actually crumble to dust. Swapping in a set of these stops on the rear of an early ND will give improved travel and decrease the chance of snap oversteer. Mazda moved to a stock bumpstop that is closer in design to this one on the RF and on 2018+ soft tops. We include these with our Koni shocks and suspension kits, something you won't find anywhere else. NA/NB/NC chassis get four, NDs get two. These are different than the V-Maxx bumpstops, but are a great replacement for those shocks. 54mm in length. We think it's a good length for a Miata at a typical lowered ride height such as with our FM springs. A shorter, stiffer bumpstop will allow more travel before you start to hit the stop, but it also means a more abrupt transition on to the stop and that translates into decreased ride quality and less consistent handling. Sold in pairs. Two pairs are needed per car.