Mason 220

The Widest of its kind! PATENTED pentagonal crossbars, 15.3 mm hardened steel. Stronger than any rounded crossbars, Double deadbolt locking mechanism for protection against twist attacks. *Mounting Bracket sold separately  

    Customer Reviews

    Based on 9 reviews
    Masoud Saeedikhou
    Better than expected

    Where I am theft is a rare assurance, but it better safe than sorry.


    I'm very grateful to have received the mounting bracket with the zip-ties. Delivery was quick. Although the bracket arrived with a minor scratch on one side of the base, it can't be seen --especially with the lock in it. It's a quality made product. So far my Seatylock U Lock feels secure without rattling much when riding my e-scooter. Thank you!

    Veronica Dye
    Great lock, easy ordering

    The lock is huge and I can lock my bike up anywhere! It's big and a little bulky, but I live in NYC and needed a big lock to feel safe locking my bike up outside. Delivery was great and easy.

    Great lock

    Very sturdy solid lock. Weights almost half of all similar size locks. Had my doubts at first as the lock rattled alot while cycling. So I added two 14mm rubber o-rings on each shackle. Fits perfectly now & no rattles while biking.

    Jack Peterson
    Sorry, but I like and don't like this mounting bracket

    What I like about this mounting bracket is that the U-lock stores quickly and easily, although I did augment the bracket with a Velcro strap on to hold the lock to the frame on the other end.

    I like the Pentagon 300 u-lock that I bought (so far). What I don't like about its mounting bracket is that it uses a strap, which stretches over time and if you cut the strap after installation it is very hard to try and get it tight on the bike frame again. Why Seatylock would use this flawed bracket mounting design is a mystery to me because a conventional bolt-on bracket would be much better (that's what my other u-lock brand uses and it's never come loose.)

    Julie Lycklama
    Great customer service

    Great product & great customer service! My bracket came with a missing piece and they sent me a new one a couple of days later, with no hassle.

    Leslie Thomas
    Strong sense of security

    See attached image. I love this lock. It gives me a strong sense of security. Thanks.

    Justin from KY
    Great for E-Bike

    Using this for my Rad Runner! This lock is a beast, seems very well manufactured. Heavy and glad e-bike is carrying the load. Also, seatylock staff was very very helpful, email response took a day or two but that is expected during current crisis. They shipped quickly and want to thank them for their support.

    Donna Lewis
    Beefy lock & GREAT customer service

    I first ordered a smaller Seatylock lock, the Mason 85/180, because of the gold rating by an independent 3rd party testing organization. It was too small, maybe because my bike is electric and the frame members are bulkier. I returned it and ordered the also-gold-rated Pentagon 300. The Pentagon is easier to use and beefy but sleek. The customer service is worth a note because it was excellent. I received an immediate and non-form-email response to my queries about the return, they credited the Mason promptly (I put it back in its packaging), shipped the Pentagon such that I got it 2 days after ordering it, and they touched base to make sure all was OK. I feel well tended.

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