H&R Trak+ wheel spacers will not only widen the track of your vehicle resulting in better handling, but, will also cosmeticaly enhance the appearance by widening the stance and filling out the wheel well. All spacers are hubcentric ensuring the best fittment possible. Comprised of an aluminum/magnesium alloy, H&R spacers are extremly durable and not to mention 70% lighter than a comparable steel product.* H&R's lengthened spacer bolts necessary for spacers over 5mm in width. Recommended bolt size: 8mm spacers=35mm bolts, 10mm spacers=37mm bolts, 12mm spacers=39mm bolts, 15mm spacers=42mm bolts, 20mm spacers=47mm bolts.