Our take
GPX PJ300B is a compact projector for an external player, with native 800 × 480 pixels and an unusually broad combination of two HDMI inputs, VGA, USB, microSD and composite AV. Its Bluetooth transmitter sends audio to an external speaker, not video to the projector. It may work for casual local playback when a small image and external power are acceptable, but the manufacturer page supplies no ANSI rating.
A portable-to-carry projector for simple external-source playback where detail and brightness are secondary..
It is not a native HD or Full HD choice, a documented battery projector, or a way to project a phone image over Bluetooth alone.
Pros & cons
What could work for you, and what to consider before buying.
What works in its favor
- GPX documents dual HDMI plus VGA, USB, microSD and composite AV on the exact model.
- The manual focus and keystone adjustment allow basic image setup.
- Bluetooth can send audio to an external speaker or headphones.
What to weigh up
- Native 800 × 480 resolution limits detail for text and large widescreen images.
- Brightness is not established as an ANSI-lumen value in the reviewed page.
- Bluetooth does not carry video, and the unit relies on an external power adapter.
The key details
| Model covered | PJ300B |
|---|---|
| Image format | Native 800 × 480 WVGA |
| Rated light output | Brightness not stated as ANSI lumens |
| Placement | 3.9–12.1 ft listed distance; dual HDMI, VGA, USB and microSD |
Performance figures are manufacturer claims. Source checked October 11, 2026. Regional models and included accessories can differ.
What the features mean for you
How much detail does the PJ300B show?
GPX lists native resolution at 800 × 480. The projector can accept several higher input formats, including 1080p, but accepting an input does not change the physical native image grid. This can be adequate for simple casual video at a modest image size, while small captions, computer text and fine detail will be limited. If a laptop is the main source, test the actual screen content at the intended viewing distance. Choose native 720p or 1080p if the image needs to carry detailed slides or a large home-cinema picture.
What can connect directly?
The official page names two HDMI inputs, VGA, USB, microSD and a 3.5 mm audio/video input. That gives the PJ300B multiple ways to work with an external player, computer, camera or older composite source. The USB and card slots do not by themselves establish a current streaming platform, so plan a separate device for services that require one. GPX also notes that an HDMI cable and some phone adapters may be needed. Confirm the exact cable path for a tablet or phone rather than assuming a wireless cast will work.
What does Bluetooth do on this model?
GPX is explicit that the built-in Bluetooth transmitter sends audio to a Bluetooth speaker or headphones; it does not send pictures or video from a phone to the projector. A video source still needs a compatible HDMI, VGA or other documented path. This distinction matters if the goal is a tidy wireless setup: Bluetooth can improve audio routing, but it does not eliminate the video cable or external player. Pair the speaker before a viewing session and verify that its audio delay and connection behave acceptably with the chosen source.
Can it fit a small room?
GPX gives a projection distance of approximately 3.9 to 12.1 feet and a viewable size up to 150 inches. The listed maximum is not a promise of useful brightness at that size, and no ANSI-labeled brightness figure was verified. Measure the distance for the desired diagonal, keep the projector level, and use the manual focus and keystone controls to align the picture. The model is not documented as UST, and its placement guidance requires real throw distance. A close-wall need or large screen in a bright room calls for a projector with clearer optical and output specifications.
How should you plan power and maintenance?
GPX describes an external AC/DC adapter and an LED bulb with a model life estimate. The adapter must be present and in working order, and the lifetime figure is not a condition report for a particular offer. Check the projector powers on without flicker, inspect focus across the image, test both HDMI ports and the card reader, and listen for abnormal fan noise. This is a small unit to carry between rooms, but it is not documented as battery-powered. Carrying a compact projector and operating without an outlet are separate requirements.
Who should consider the PJ300B?
The PJ300B fits someone who already has a compatible external source, wants varied wired inputs and can accept WVGA detail. It is a weak fit for a user who expects phone-to-projector Bluetooth video, a built-in app store, strong daylight use or a fine-text presentation image. Check the exact unit, adapter, remote and input operation before buying. The old candidate ASIN is kept as roster history only; the tagged exact-model search lets you compare current offers without treating a historic identifier as a verified listing.
What else to compare
Compare a native 720p or Full HD projector for larger detailed images, or a battery model when projection away from an outlet is essential.
Before you buy
Does accepting 1080p input make it native Full HD?
No. GPX lists a native 800 × 480 image; supported input formats are scaled to that panel.
Can Bluetooth project a phone's video?
No. GPX says Bluetooth transmits audio; video needs an HDMI adapter or another supported input.
Does the projector have a documented ANSI rating?
No ANSI-labeled value appears in the reviewed GPX page, so brightness remains unknown for ANSI filtering.
Is the PJ300B battery-powered?
GPX lists external adapter power; the reviewed source does not document built-in battery operation.
Where can I check the current price?
Use the Amazon link for current offers. Check the exact model, seller, product condition, delivery, and return terms. This page does not display a live price or confirm stock.
Sources & review basis
We use the following manufacturer documentation for the product features above. Our suitability notes and buying advice are editorial judgments based on those features, not measured performance results.
- GPX official PJ300B product page and connection guide ↗ — checked October 11, 2026.
- GPX official Mini Projector PJ300B page and FAQ ↗ — checked October 11, 2026.
The decision
Choose PJ300B for its input flexibility and audio Bluetooth only when its WVGA panel and external-power setup match the actual use.
Is it the right fit?
Check the exact model and today’s offers on Amazon.