AX-940

1. Overview

The Sanwa Denshi SDM-18 is an 18 mm round snap-in arcade button with a built-in microswitch — Sanwa's small-format button used for service / coin / test / menu functions on arcade cabinets (the small buttons on the coin door or admin panel, not the main play buttons). It shares Sanwa's quality microswitch feel in a compact 18 mm size, available in several colors (white, black, etc.).

2. User Sentiment

The go-to small service button for arcade/candy-cab and custom builds — Sanwa quality and reliability in the 18 mm size used for coin/service/test. Little "sentiment" beyond it being the standard for the role; the main note is the small 18 mm cutout (distinct from the 24 mm start/aux and 30 mm main buttons).

3. Real-World Applications

Service, coin, test, and menu buttons on arcade cabinets, candy cabs, and custom controllers — the small admin/utility buttons (often behind the coin door or on a service panel).

4. Technical Specifications

• Type: 18 mm round arcade service/coin button, snap-in
• Switch: built-in Sanwa microswitch
• Mounting: snap-in (18 mm cutout)
• Colors: several (white, black, etc.)

5. Ordering & Compatibility

Fits 18 mm panel cutouts (smaller than the 24 mm start/aux and 30 mm main buttons). Sold by arcade specialists (Focus Attack, Paradise Arcade, Arcade Shock, Japanese retailers). Confirm the 18 mm cutout and color/quantity for the service-panel layout.

6. Known Issues

No reliability concerns — Sanwa quality. Practical notes: confirm the 18 mm cutout (don't confuse with 24/30 mm buttons), and verify the microswitch tab size matches your wiring. Beware clones for genuine Sanwa feel/durability.