Transistor tester case

Title suggestion: Transistor Tester Case (14500 Li-ion Component Tester Enclosure) — Screwless, Snap-Fit Design

Description:

A 3D-printable enclosure for the common AliExpress/Banggood-style transistor and component tester board (GM328/M328-type), designed to fit the PCB shown in the photos — identifiable by the "Battery Model NO.: 14500, Cell Type: Li-ion, Voltage: 3.7V, Rechargeable: Yes" markings on the back.

Key features:

• No supports required — every part prints clean straight off the plate.
• No screws needed for assembly. The PCB mounting holes slide onto dedicated posts inside the case, and the board is securely held in place once the case is closed.
• Snap-fit closure — the top and bottom halves click together firmly without any fasteners.
• Built-in disassembly slot — a slim gap is molded into the seam specifically sized for a knife blade, letting you pry the case open cleanly whenever you need to access the board again.
• Field-tested design — printed, assembled, and used in practice.

Compatibility:
This case is designed for boards with:

• A 14500 Li-ion cell holder (rechargeable, 3.7V)
• Three probe/test sockets (TP1–TP3) along the bottom edge
• Four corner mounting holes
• Side connector notch for USB/charging port

Since these tester boards are sold under many brand names but usually share the same PCB layout, this case should fit most common clones with the 14500-battery variant. Always check hole spacing against your own board before printing, as minor revisions exist between suppliers.

Print settings:

• Material: PLA or PETG
• Layer height: 0.2mm
• Infill: 15–20%
• Supports: not required

Assembly:
Place the PCB onto the mounting posts using the existing corner holes — no screws needed. Close the case halves together until the snap-fit tabs click into place. To open for maintenance, insert a knife blade into the pry slot along the seam and gently twist.