{"product_id":"taillight-bulb-12v-21w-5w-csc-go-qmb139-scooters","title":"Universal Parts BAY15D Tail \u0026 Brake Light Bulb - 12V 21\/5W","description":"\u003ch2\u003eDescription\u003c\/h2\u003e\u003cp\u003eThis \u003cstrong\u003eUniversal Parts tail and brake light bulb\u003c\/strong\u003e restores running-light and brake-light illumination in one straightforward replacement. Its dual-filament 12V 21\/5W design fits matching BAY15d sockets on scooters and other powersports equipment, including CSC go. scooters and compatible 139QMB and GY6 models.\u003c\/p\u003e\u003ch2\u003eFeatures\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eTwo lighting functions:\u003c\/strong\u003e A 5W filament provides the running light, while the 21W filament provides the brake light.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eUniversal socket-based fit:\u003c\/strong\u003e Suitable for scooters and other powersports equipment requiring a 12V 21\/5W BAY15D bulb.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDual-filament incandescent design:\u003c\/strong\u003e Clear glass bulb with separate tail- and brake-light filaments.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBAY15d bayonet base:\u003c\/strong\u003e Double-contact base with offset-height retaining pins for a matching socket.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eSpecifications\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrand:\u003c\/strong\u003e Universal Parts\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePart number:\u003c\/strong\u003e 0900-4021\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAlternate references:\u003c\/strong\u003e 138-37-10PCS, 138-37-1PC\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eVoltage:\u003c\/strong\u003e 12V\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBrake-light filament:\u003c\/strong\u003e 21W\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRunning-light filament:\u003c\/strong\u003e 5W\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBase:\u003c\/strong\u003e BAY15d (1157-style), double-contact bayonet\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBase diameter:\u003c\/strong\u003e 15 mm\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRetaining pins:\u003c\/strong\u003e Offset in height, one higher than the other\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBase contacts:\u003c\/strong\u003e 2\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eLight source:\u003c\/strong\u003e Dual-filament incandescent\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eGlass:\u003c\/strong\u003e Clear\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eQuantity:\u003c\/strong\u003e 1 bulb\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eModel Fitment\u003c\/h2\u003e\u003cp\u003eUniversal replacement for scooters and other powersports equipment using a BAY15d socket and requiring a 12V 21\/5W dual-filament tail\/brake bulb. Commonly found on 139QMB and GY6 model scooters; fitment is determined by the bulb socket, voltage, wattage, and housing clearance, not the engine alone.\u003c\/p\u003e\u003ctable\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eApplication\u003c\/th\u003e\n\u003cth\u003eFitment\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eChicago Scooter Company\u003c\/td\u003e\n\u003ctd\u003eCSC go. scooters\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e139QMB-based 50\/80cc scooters\u003c\/td\u003e\n\u003ctd\u003eMatching BAY15d tail\/brake sockets; includes 139QMA, 139QMB, 1P39QMB, 1P39QMA-2, YN139QMB, JJ1P39QMB, 139FMA-2, BD1P39QMB, BN139QMB, 147QMD, and other QMA\/QMB applications when the bulb specifications match\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eGY6 scooters\u003c\/td\u003e\n\u003ctd\u003eModels requiring a 12V 21\/5W BAY15d tail\/brake bulb\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOther powersports equipment\u003c\/td\u003e\n\u003ctd\u003eAny make or model with a matching BAY15d socket, 12V 21\/5W requirement, and adequate bulb clearance\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eHow to identify the base:\u003c\/strong\u003e The BAY15d (1157-style) base is 15 mm in diameter, has two electrical contacts on the bottom, and uses two retaining pins at different heights. Compare these details with your original bulb and socket, then confirm the 12V 21\/5W requirement and bulb clearance. BAY15d and BA15d are different base specifications; this bulb requires a BAY15d socket.\u003c\/p\u003e\u003ch2\u003eProduct Diagrams\u003c\/h2\u003e\u003cul class=\"az-content-resources\"\u003e\u003cli\u003e\n\u003ca href=\"\/search?view=az-assembly\u0026amp;q=76\"\u003eQMB139 LIGHTS ASSY\u003c\/a\u003e \u003cspan\u003eCallout 8\u003c\/span\u003e\n\u003c\/li\u003e\u003c\/ul\u003e","brand":"Universal Parts","offers":[{"title":"Default Title","offer_id":67964634300737,"sku":"0900-4021","price":3.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1011\/7785\/2225\/files\/az-p012-10169-0-0900-4021_2da4ea5f-f4aa-4964-9636-06d671cfd6ef.jpg?v=1792558025","url":"https:\/\/azscooterparts.com\/products\/taillight-bulb-12v-21w-5w-csc-go-qmb139-scooters","provider":"AZScooterParts","version":"1.0","type":"link"}