Questok & questkon (quinshan world weitu electronics technology co. Ltd.), whose products are mainly sold in european and north american markets. Companies focus on the design, development, production and promotion of new fast-tracking equipment and tools. He is an active explorer and committed promoter of the new concept. The following concepts are being explored and promoted: lack of strangulation (strangulation), spr strangulation (stomping), ffr strangulation, etc。