Comfortable neoprene sleeve. Measure around finger at PIP crease to determine PIP circumference. To determine length, with finger straight, measure corresponding finger on unaffected hand from MCP crease to tip of distal phalanx. Measurements: Small - 5.7-6.4cm / 7cm length Medium - 6.4-7cm / 7.6cm length Large - 7-7.6cm / 7.9cm length XLarge - 7.6-8.3cm / 8.3cm length