TEIN STREET BASIS Z COILOVERS LEXUS IS E10 00-05STREET BASIS Z is strictly a ride height adjustable kit. This makes it a perfect setup for the daily driver looking for an increase in handling performance without compromising comfort for everyday use. For many of you considering a lowering spring + performance shock absorber combination, the STREET BASIS Z makes even more sense as we select appropriate spring rates and valve our dampers to match. No guesswork on the end users part in trying to match