Measure the center-to-center distance between your two pulleys, then calculate the required belt circumference using the standard formula: C = 2 × center distance + π × (D1 + D2) / 2. The model number directly indicates the belt circumference in millimeters — for example, HTD5M-1200 has a 1200mm (≈47.2") circumference. Choose the model closest to your calculated requirement.

Torque capacity depends on belt width, the number of teeth in mesh with the pulley, and operating speed. Generally, wider belts (25–30mm) handle higher torque loads. For typical light-to-medium duty applications such as CNC routers and 3D printer gantries, HTD5M belts generally perform well within their rated range. Consult your drive system's torque requirements and compare against the belt manufacturer's load tables to confirm suitability.

The polyurethane body typically offers better resistance to oils, mild chemicals, and moisture compared to standard rubber timing belts. However, prolonged direct UV exposure or extreme temperature conditions may affect belt performance over time. For outdoor or harsh-environment installations, verify the operating temperature range and consider UV shielding where applicable.

HTD5M belts require pulleys with the HTD5M tooth profile and 5mm pitch. They are not interchangeable with GT2 (2mm pitch), T5 (5mm trapezoidal), MXL, or other profiles — even if the pitch spacing appears similar. Always confirm that both your belt and pulley share the same HTD5M profile designation before installation.

Belt width selection depends on the torque and lateral stiffness required by your drive. As a general guide: 10–15mm is typically sufficient for light-duty positioning systems such as 3D printer axes; 20–25mm is generally recommended for medium-duty CNC or robotic drives; 30mm provides additional load capacity for heavier conveyor or multi-axis systems. Always verify against your specific drive torque calculations.

These are three distinct tooth profiles that are not interchangeable: HTD5M uses a rounded (curvilinear) tooth designed for higher torque with reduced stress concentration; GT2 uses a modified curvilinear profile optimized for precision positioning at lower backlash; T5 uses a trapezoidal tooth profile suited for general power transmission. Match your belt profile exactly to your pulley profile for correct engagement.

The model number encodes the belt's key dimensions. For example, HTD5M-1200 means: HTD profile, 5mm pitch, 1200mm circumference. The number after the dash is always the belt circumference in millimeters. To convert to inches, divide by 25.4 — so 1200mm ÷ 25.4 ≈ 47.2". Select the model that matches your calculated required circumference.