This is a Boom Racing 2-stage foam insert for 1.55" wheels and 4.19" RC crawler tires. They are two stage foams, open cell outside and closed memory cell inside.
Specification:
Outer Compound: Soft
Inner Firmness: Hard
Size:
Open foam: 103.0mm x 35mm
Closed foam: 71.0mm x 29mm
Includes:
2x 4.19" 1.55 2-Stage Foam Insert
Product weight: 28.00 grams
Package size: 11.00 x 22.00 x 4.00cm
Factory description: Boom Racing 1.55" Dual 2-Stage Open (Soft) / Closed (Hard) Cell Foam Rock Crawling Inserts for 4.19in (106mm) RC Crawler Tires (2)
Manufactured by Boom Racing
Manufacturer number: BRTR25503SH
