GE 20839 Q50MR16C/NSP15

The GE ConstantColor Precise EXT is a high-performance 50W 12V open-face halogen MR16 narrow spot lamp delivering a tight 15° beam with 9,100 CBCP for precise accent, display, and architectural highlight applications. Featuring GE's ConstantColor Precise reflector coating technology for consistent white light output throughout its 6,000-hour rated life, UV control through the reflector coating to protect sensitive merchandise and artwork, and a GX5.3 bi-pin base, this ANSI EXT-coded lamp is the premium specification for retail showcases, jewelry cases, museum and gallery spotlighting, and track accent systems requiring long-life color stability at high beam intensity.

ADL Supply Expert Application & Replacement Guide

The GE ConstantColor Precise EXT is primarily specified by lighting designers, visual merchandising teams, and electrical contractors for high-end retail jewelry and fashion showcases, museum and gallery accent tracks, architectural feature lighting, and commercial display applications where both long lamp life and consistent color rendering over lamp life are specification priorities. The ConstantColor Precise reflector coating maintains consistent warm white output throughout the 6,000-hour lamp life — standard MR16 reflector coatings progressively shift toward green or amber tint as the lamp ages, which is visually perceptible in display and retail environments where color accuracy directly affects merchandise presentation quality. The UV control in this lamp is achieved through the reflector coating — it limits UV energy in the forward beam direction without requiring a physical front cover glass, which would reduce beam intensity. Because there is no integral cover glass, this is an open-face lamp and must be installed in an approved enclosed fixture that provides a UV-filtering front lens if UV containment beyond the reflector coating level is required for sensitive artwork or merchandise. This lamp requires a 12V low-voltage transformer rated for 50W halogen MR16 loads and is fully dimmable with compatible low-voltage dimmers.

Before You Order

Detailed Product Specifications

• Brand: GE Lighting
• Product Line Series: ConstantColor Precise — Halogen MR16 Narrow Spot
• ANSI Code: EXT
• UPC Barcode: 043168994286
• Core Technology: Tungsten-Halogen MR16 Open Face — ConstantColor Precise Reflector Coating
• Wattage: 50W
• Operating Voltage: 12V Low Voltage
• Luminous Flux: Approximately 750–890 lm
• Center Beam Candlepower (CBCP): 9,100 cd
• Beam Angle: 15° Narrow Spot
• Color Temperature (CCT): 3050K Warm White
• Color Rendering Index (CRI): 100 Ra
• Base Type Configuration: GX5.3 Bi-Pin (5.3mm round pin spacing)
• Front Glass: Open Face — No Integral Cover Glass
• UV Control: Reflector coating — limits UV in forward beam
• Maximum Overall Length (MOL): 1.875 inches (47.6mm)
• Reflector Diameter: 2.0 inches (50.8mm) — MR16
• Rated Average Lifespan: 6,000 Hours
• Burn Position: Universal — Any Orientation
• Dimmable: Yes — with compatible 12V low-voltage dimmer
• Mercury Content: None — standard e-waste disposal applies

Operation, Safety & Mounting Compliance

12V Transformer, ConstantColor Technology & Open Face Requirement

This lamp requires a 12V step-down transformer rated for 50W continuous halogen MR16 load — both magnetic (toroidal) and electronic low-voltage transformers are compatible, provided the transformer's minimum load threshold is met and it is rated for halogen loads. The lamp cannot be direct-wired to 120V line voltage. The ConstantColor Precise reflector coating provides color stability throughout lamp life by maintaining consistent spectral output from the reflector surface as the lamp ages — standard multi-layer dichroic reflector coatings can shift color output as the coating is exposed to thermal cycling over thousands of hours. Because this is an open-face design, keep combustible materials clear of the beam and fixture; do not use a lamp with a scratched or cracked envelope. For applications requiring complete UV containment at the fixture face — such as rare artwork or light-sensitive documents — confirm that the fixture provides a UV-filtering front lens in addition to the lamp's reflector coating UV control.

Quartz Handling & Disposal

Never handle the quartz envelope or reflector body with bare skin — skin oils create localized hot spots that accelerate premature envelope failure. Always relamp using clean cotton gloves or a lint-free cloth. Turn off power and allow a minimum 15-minute cool-down before relamping. Dispose of spent lamps in a closed container. This lamp contains no mercury; standard electronic waste disposal applies.

Industry Cross-Reference Data

• Osram Sylvania: 58527 / 50MR16/NSP (equivalent 50W 12V GX5.3 15° narrow spot MR16)
• Philips: 415745 / 50MR16/15°/EXT (equivalent ANSI EXT 50W 12V narrow spot)
• Ushio: 1000838 / EXT 50W 12V GX5.3 (equivalent ANSI EXT narrow spot MR16)
• Legacy Cross-Reference: Premium replacement for ANSI EXT-coded 50W 12V GX5.3 15° narrow spot MR16 halogen lamp positions in retail showcase, jewelry display, gallery track, and architectural accent fixture hardware — with superior color stability vs. standard MR16 narrow spot alternatives

Bulk Commercial Lighting Supply & Project Support

ADL Supply delivers commercial-volume logistical fulfillment, tiered commercial contractor discounting strategies, and full pallet project quoting options to electrical accounts across the United States.

For formal wholesale inquiries, volume pricing modifications, or manufacturer spec sheet documentation, reach our commercial branch directly at 1-800-235-3489. We are your commercial supply partners as an authorized wholesale Lighting Distributor In Doral, Florida.