Rocker switches are widely used in household appliances, industrial machinery, automotive dashboards, outdoor control panels, marine electronics, and RV power systems. For B2B buyers, selecting the housing material is not just about cost — it directly impacts mechanical strength, thermal resistance, dimensional stability, and cold weather performance.

In outdoor, automotive, cold chain, or alpine conditions, low temperature brittleness is a critical concern for plastic housings. This article compares the three most common engineering plastics for rocker switch housings — Nylon (PA), Polycarbonate (PC), and Polyphenylene Oxide (PPO) — focusing on their brittleness temperatures, performance features, and real-world examples.

✅ 1. Why Does Low Temperature Brittleness Matter?

For indoor devices, rocker switches usually operate from -10°C to +60°C, which rarely tests a plastic’s limits. But in these situations, cold-induced cracking is a real threat:

• Outdoor lighting and power control in winter (-30°C to 0°C)

• Automotive dashboards, RVs, boats in cold climates (-40°C possible)

• Cold storage or cold chain control panels (-20°C or lower)

• Agricultural equipment in northern regions

Near its brittleness point, a plastic loses impact strength, so parts like clips, covers, or rocker levers can crack under minor stress. For OEMs, choosing the right housing plastic avoids costly breakage, returns, and warranty claims.

✅ 2. Material Comparison: Nylon vs. PC vs. PPO