Check the listing for details. 4mm Inline Mechanical Turbo Boost Gauge Restrictor Damper Hose Joiner - Psi Bar. Condition: New. Listed at 11.74 USD. ***VERY FAST DELIVERY*** ALL ORDERS SENT SAME OR NEXT DAY This sale is for 1 x Norma 4mm Inline Boost Gauge Damper for use when installing mechanical boost or vacuum gauges, these Inline dampers are used to cure the needle vibration associated with mechanical pressure gauges installed on turbocharged petrol and diesel engines. This is a high quality Norma inline hose joiner with an inbuilt brass restrictor so very simple construction and extremely easy to install. The inline damper simply fits inline on your vacuum/pressure hose that goes direct to the back of your boost gauge. This inline damper will help reduce the infamous needle vibration on mechanical boost gauges and can also be used to stop unrestricted pressure from damaging internal diaphragms on expensive boost sensors if used with electrical gauges. Please note that some cheaper/poor quality Chinese gauges may require further restriction to totally eliminate vibration, this is because of the low quality mechanisms used when manufacturing these cheap gauges. This product has been optimised specifically so that there is no detriment to gauge performance and various tests with recognised quality gauge brands have proven this product to be a must for any mechanical pressure gauge. *This inline boost gauge damper is 4mm, there is also a 5mm boost gauge damper available to purchase in our other Ebay items. R-Spec Performance Products Ltd is probably the largest gauge supplier in the UK and we hold everything in stock ready for immediate dispatch. We have 1000's of gauges & pods etc in stock so please check our other Ebay items or just contact us with your requirements so that we can list it for you. For any further information on this product or customer services please call 01869 327237 Listing and template services provided by inkFrog