581 Bulb 12V 21W Amber PY21W - Indicator Light Bulb BAU15s - Classic

Standard amber-colored indicator bulb designed for automotive front and rear turn signals with offset-pin bayonet base.
The Classic 581 bulb (also known as PY21W) features a BAU15s offset-pin base that ensures it cannot be replaced by a standard white P21W bulb, providing safety and compliance. ECE Regulation 37 approved and road legal for UK and European vehicles.

Key Features

• Offset-Pin Design: BAU15s base with pins at 150°/150° prevents incorrect bulb installation
• Amber Light Output: Orange/amber color ensures compliance with indicator regulations
• High Vibration Resistance: Durable halogen construction designed to withstand automotive vibration and temperature extremes
• Bayonet Fitting: 15mm diameter BAU15s base for secure, twist-and-lock installation
• Road Legal: ECE Regulation 37 approved for UK and European compliance
• Single Filament: Reliable halogen technology for consistent 21W performance
• Wide Compatibility: Suitable for most European vehicles requiring amber indicator bulbs

Technical Specifications

Application & Usage Guide

Primary Application:

• Front indicator lights (turn signals)
• Rear indicator lights (turn signals)
• Side repeater indicators (on some vehicles)

Also Known As: PY21W, 581 indicator bulb, BAU15s amber bulb

Why Offset Pins? The BAU15s base features offset pins (150°/150°) rather than opposite pins (180°/180°). This design prevents installation of incorrect bulb types - you cannot accidentally fit a white P21W bulb (BA15s) into a PY21W socket, ensuring your indicators remain amber as required by law.

Installation: Align the offset pins with the socket slots, insert the bulb, and twist clockwise to lock in place. The offset design ensures correct orientation. Always ensure the ignition is off before replacing bulbs and replace in pairs for consistent appearance.

Compatibility: Suitable for most European vehicles with 12V DC electrical systems requiring amber indicator bulbs with BAU15s offset-pin base. Check your vehicle handbook or existing bulb to confirm 581/PY21W fitment before purchase.

Important Safety & Compatibility Information

• Always verify bulb type in your vehicle handbook before purchasing
• Switch off ignition and allow bulbs to cool before handling
• Do not touch glass with bare hands; use a clean cloth to avoid oil contamination
• Ensure bulb is correctly seated and twisted to lock in socket
• Replace indicator bulbs in pairs for consistent light output and appearance
• Amber bulbs are required for indicators in the UK and EU - do not substitute with clear or white bulbs
• The offset-pin design prevents incorrect bulb installation for safety
• Dispose of used bulbs responsibly at household waste recycling centres
• Keep out of reach of children

SHIPPING & RETURNS

Shipping:

• Fast UK delivery available
• Local collection option at checkout
• Orders dispatched within 1-2 working days
• Tracked shipping on all orders

Returns:

• 14-day return policy on unopened products
• Items must be unused and in original packaging
• Contact gtmotorspart@outlook.com for return authorization
• Opened bulbs are non-returnable for safety and hygiene reasons

WHY CHOOSE US

• Trusted Quality: Genuine OEM-approved parts and premium fluids from authorized suppliers
• Competitive Pricing: Best value on premium automotive oils and maintenance products
• Fast Local Delivery & Collection: Quick dispatch with flexible delivery and collection options across the UK
• Friendly Support: Expert advice and customer service from automotive specialists