Osram FLK/X 575W 115V G9.5 NAED 54551

Product Overview

Osram 54551 FLK/X — 575W 115V Professional Stage Halogen Lamp, 3200K, G9.5 Bipin | ETC Source 4

The Osram 54551 FLK/X is a 575-watt, 115-volt professional stage and studio halogen lamp from Osram, designed for theatrical ellipsoidal spotlights, studio fixtures, and professional entertainment lighting. With a G9.5 bipin base, ANSI code FLK, CC-8 filament, 3200K color temperature, CRI 100, 10,000 initial lumens, universal burn position, and a 2,000-hour rated life, this lamp is the industry-standard replacement for the ETC Source 4 and compatible professional stage fixtures on 115V circuits. Dimmable with traditional amber shift. Sold in cases of 12. Verify ANSI code, voltage, and base type against your fixture specification before ordering.

Wattage

575W

Stage Halogen

Lumens

10,000 lm

Initial Output

Color Temp

3200K

CRI 100

Base

G9.5

Bipin

Rated Life

2,000 hrs

Average Life

Technical Specifications

Brand	Osram
Osram Product Number	54551
Global Order Reference	FLK/X 575W 115V
ANSI Code	FLK
Lamp Type	Halogen — Single-Ended, Professional Stage & Studio
Wattage	575W
Voltage	115V AC
Initial Lumens	10,000 lm
CRI	100
Color Temperature	3200K (Tungsten White)
Base Type	G9.5 Bipin
Filament	CC-8
Light Center Length (LCL)	2.325"
Burn / Operating Position	Universal
Start Type	Instant — full output immediately; dimmable with amber shift
Rated Average Life	2,000 hours
Length	101mm (approx. 4")
Diameter	0.625" (15.9mm)
EAN / UPC	4062172146715
Packaging	12 per case

Product Overview

The Osram 54551 FLK/X is the professional entertainment industry's standard 575W stage halogen lamp, specified for the ETC Source 4 ellipsoidal spotlight and a broad range of compatible theatrical, studio, and entertainment fixtures on 115V circuits. The CC-8 filament provides a compact, concentrated source suited to the ellipsoidal reflector geometry of professional spotlights, where precise filament positioning produces clean beam cutoffs and sharp gobo projection.

At 3200K with CRI 100, the FLK delivers full-spectrum halogen output for accurate color reproduction through theatrical gels and photographic filters. Luminous flux remains nearly constant over lamp life — the lamp delivers consistent, predictable output from first use through rated life. Dimmable on standard theatrical dimmer systems with traditional amber shift as intensity decreases. Instant on at full output — no warm-up required for cue-accurate live production use.

FLK vs. HPL note: The ETC Source 4 accepts both FLK and HPL lamps depending on fixture variant. FLK and HPL have different Light Center Length (LCL) values and produce different beam characteristics in the same fixture. Confirm which lamp your specific Source 4 variant requires before ordering.

Compatible Fixtures

ETC Source 4
Altman 360Q 6x9
Strand SL Series
L&E AQ61ZM Zoom
Berkey Colortran 5/50

Compatible Applications

Theatrical stage lighting — Primary lamp for professional ellipsoidal spotlights in theatres, performance spaces, and educational stage facilities.
Concert and touring lighting — Standard stock lamp for 575W ellipsoidal and profile spotlights on touring production rigs.
Studio, TV, and film production — 3200K tungsten-balanced output for camera-balanced studio lighting rigs.
Professional photography and club/disco lighting — High-output halogen source for photography fixtures and entertainment venues.
Event and corporate production — Standard inventory lamp for professional event lighting and corporate AV production.

Before Ordering — Verify

ANSI Code: Confirm your fixture specifies FLK. FLK is 575W/115V with G9.5 base — not interchangeable with FEL (1000W/120V), HPL (575W/120V, different LCL), or other 575W designations.
Voltage: Confirm your fixture circuit is 115V. Do not install in 240V fixtures.
Base Type: Stage fixtures may specify G9.5, GY9.5, or GX9.5 — confirm the exact base designation with your fixture manufacturer's lamp specification documentation.
FLK vs HPL: Confirm which lamp your specific ETC Source 4 or compatible fixture variant requires — FLK and HPL are not interchangeable due to different LCL values.

Cross Reference

Ushio 1002196
GE 88548
Thorn HX600

Safety and Handling Guidelines

Operational surface temperature exceeds 400°C. Use thermal-rated gloves for all handling and lamp replacement. Allow at least 15 minutes cool-down after switch-off before attempting lamp replacement.
Do not touch the quartz envelope with bare hands. Skin oils cause hot spots leading to premature failure. Use thermal-rated gloves or a lint-free cloth. Clean with isopropyl alcohol if touched accidentally.
Approved enclosed luminaires only: Use only in UL-certified fixtures designed with appropriate protective shields or grids to contain lamp parts in the event of bursting and to prevent UV radiation from escaping during operation.
UV radiation warning: High UV output during operation. Use only in fixtures with appropriate UV-protective shielding.

Compliance

ANSI FLK certified. UL Listed. RoHS Compliant.
Verify Prop 65 requirements with the Osram manufacturer specification sheet prior to use in regulated installations.