In early June, at the beginning of the annual Pride month that celebrates LGBTQ people and pushes for gay rights and equality around the world, blink-182's Mark Hoppus took aim at the notion of a planned "Straight Pride" parade in Boston. To instead support LGBTQ communities, he pledged to auction a bass and donate all the proceeds to The Trevor Project, an organization that focuses on crisis intervention efforts among lesbian, gay, bisexual, transgender, queer, and questioning youth.

Today, that auction begins. The instrument up for sale is a custom Fender Mark Hoppus Precision Bass that he used to write much of the group's 2003 untitled album (sometimes referred to as the self-titled album). And next week—on the day the custom bass auction ends—Hoppus will be launching The Official Mark Hoppus of blink-182 Reverb Shop to sell nearly 80 more instruments and pieces of gear from his collection.

"We call this plaid bass Groundskeeper Willie. I wrote a great deal of the bass riffs for the [2003] untitled album on this bass. It has the sticker of the unicorn on there and the pink Famous Stars and Straps keychain that has been on here for the past decade and a half," Hoppus said of the bass guitar. "I’m auctioning it off to raise money for the Trevor Project, which is a great organization doing great work."

Mark Hoppus' "Groundskeeper Willie" Fender Custom Shop Precision Bass Bid Now on Reverb

The auction starts now and runs through July 8. Go here now to bid. Hoppus will also donate an additional $5,000 on top of the winning bid.

As the Groundskeeper Willie auction wraps up on July 8, fans will also have the chance to own nearly 80 pieces of gear used and played by Hoppus in The Official Mark Hoppus of blink-182 Reverb Shop.

It's important to note: These items are not part of an auction. They will be sold on a first come, first served basis to the quickest buyers. Don't miss out: Sign up with your email in the box below to be notified as soon as The Official Mark Hoppus of blink-182 Reverb Shop launches.

The shop will feature a wide variety of guitars, basses, and pro audio equipment used during blink-182's recording sessions and live performances, including:

A Fender Precision Bass used on tour, which features a custom octopus drawing by Craig Christy of Ray Gun Tattoo

A custom-painted Blue Microphones tube condenser mic that Hoppus says has "been a staple of my studio setup ever since Jerry Finn told me to buy [it] on Enema of the State ."

." A pair of Avalon U5 DI boxes and preamps used extensively by Hoppus. "These were the direct pre- and post-amp sound of my live show since 2001. These have been around the world several times," he says.

An Ampeg SVT Classic amp that sat in Hoppus’ live setup for nearly a decade. “This amp has literally been around the world. It has been everywhere, sounds great, and is well road-worn,” Hoppus said.

A dozen API 512C preamps from Hoppus’ home studio. According to Hoppus, the preamps traveled to the UK with him and were used to record the PAWS album No Grace .

. A 1972 Fender Precision bass guitar, an Analog Systems 8000 Modular synthesizer, two API 500VPR Lunchboxes, two Chandler Limited: LTD-2 compressors, and more

Scroll through our gallery to see just some of the items that will be available when The Official Mark Hoppus of blink-182 Reverb Shop goes live on July 8. If you're interested in learning more about The Trevor Project or making a direct donation, visit its website here.