Product description：
TypeA: Black color
Type F: Transparent upgrade (with explosion-proof ring yellow) 
TypeE: Fluorescent upgrade (with explosion-proof ring blue) 
Material: high-strength alloy
Internal Diameter: 3.8cm
Length: 32cm

Feature:
1.Made of high-strength alloy, you don't have to worry about rusting.
2.The outer ring adopts a polygonal design, which greatly improves the strength of the cylinder.
3.The bottom of the cylinder is designed with a drainage hole, which can effectively discharge the moisture in the cylinder and keep the cylinder dry.
4.The high-transparency version adopts transparent ABS material, which improves light transmittance while maintaining plasticity and chemical stability.
5.It is suitable for various geology such as sand and gravel ground, hard land, reservoir stone joints, etc., and the bottom is firmly supported and protected.