These Excalibur Springs are full-length replacement main springs, offering a range of FPS options for your Sillybutts Excalibur. 

FEATURES:
• Excalibur Springs
• Squared/flat on both ends for easier use
• Tune the FPS of your Excalibur
• FPS was primarily measured with short darts

INCLUDES: 
• 1 Excalibur Spring of your choice

PERFORMANCE:
Average FPS with short darts + 0.527 x 12in barrel
• 100 (5) FPS with a 1.6 x 280mm spring (K31)
• 132 (6) FPS with a 2.0 x 255mm spring (788)
• 205 (7) FPS with a 2.0 x 280mm spring (K25)

Average FPS with full-length darts + 0.527 x 12in barrel
• 103 (5) FPS with a 1.6 x 280mm spring (K31)
• 131 (4) FPS with a 2.0 x 255mm spring (788)
• 183 (4) FPS with a 2.0 x 280mm spring (K25)

SPECS
• Material: USA-made spring-tempered steel
• Type Compression
• Dimensions:
     Spring Gauge: 1.6-2.0mm
     Length: 255mm-280mm
     Outer Diameter: 19-25mm
     Coils: varies
• Squared: Both Ends

LINKS:
• More Springs