Sprint resistance off-ice training

[romdj 26]

Hello everyone,

So I always thought of a device for practicing explosiveness off the sprints. And then I saw a device rocked by PK but I cannot find a brand/model/reference anywhere. Only thing I know is that it is not an elastic band!

My question is if someone in the community know anything about such a device, I'd be very interested in knowing what it is. Thanks!

For reference here's the training tool I'm talking about:

https://www.instagram.com/p/Bj7pES2ABx_/?utm_source=ig_share_sheet&igshid=to8rx5e8b04v

https://www.instagram.com/p/BlQTe_PAm5p/?utm_source=ig_share_sheet&igshid=nxwmn7ncxdng